Статті в журналах: "Estuarine ecology New Zealand"

1

Lill, Adrian W. T., Aparna Lal, and Gerard P. Closs. "Life history and reproduction of two abundant mysids (Mysidacea: Mysidae) in an intermittently open New Zealand estuary." Marine and Freshwater Research 61, no. 6 (2010): 633. http://dx.doi.org/10.1071/mf09085.

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Mysids typically form a large proportion of the hyperbenthic faunal biomass in estuaries and are central to the functioning of estuarine food webs. The population dynamics, annual life histories and reproductive effort of two common temperate estuarine mysids, Tenagomysis chiltoni and T. novae-zealandiae, are described in the intermittently open Kaikorai Lagoon, New Zealand. Mysids were sampled by night, monthly from September 2003 to September 2004. Both species completed their life cycles in the lagoon. There was an apparent spatial separation of breeding populations, with T. chiltoni prevalent in the upper lagoon and T. novae-zealandiae dominating the lower lagoon. Densities were lowest in late winter and peaked in late summer/early autumn for both species. Both species exhibited multivoltine life cycles, with breeding peaks occurring in October 2003, December 2003 and February/March 2004 for T. novae-zealandiae, and October/November 2003 and February/March 2004 for T. chiltoni. Breeding strategy for both species varied over the year with the adult size, brood size and the reproductive effort of both T. novae-zealandiae and T. chiltoni all being highest in spring. The life histories of both T. novae-zealandiae and T. chiltoni in the Kaikorai Lagoon are comparable to life histories described for other temperate estuarine mysid species in large open estuaries, and were not significantly modified to cope with the unpredictable demands of life in an intermittent estuary.

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2

Roper, David. "Benthos associated with an estuarine outfall, Tauranga Harbour, New Zealand." New Zealand Journal of Marine and Freshwater Research 24, no. 4 (December 1990): 487–98. http://dx.doi.org/10.1080/00288330.1990.9516440.

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3

Gibbs, M. M. "Morphometrically induced estuarine phytoplankton patchiness in Pelorus Sound, New Zealand." New Zealand Journal of Marine and Freshwater Research 27, no. 2 (June 1993): 191–99. http://dx.doi.org/10.1080/00288330.1993.9516557.

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4

Plew, David R., John R. Zeldis, Ude Shankar, and Alexander H. Elliott. "Using Simple Dilution Models to Predict New Zealand Estuarine Water Quality." Estuaries and Coasts 41, no. 6 (March 13, 2018): 1643–59. http://dx.doi.org/10.1007/s12237-018-0387-6.

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5

Lill, Adrian W. T., Gerard P. Closs, Candida Savage, and Marc Schallenberg. "Annual secondary production of two estuarine mysid species (Mysidacea: Mysidae) inhabiting an intermittently closed estuary, south-eastern New Zealand." Marine and Freshwater Research 62, no. 7 (2011): 823. http://dx.doi.org/10.1071/mf10274.

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Estimates of secondary production are essential to understanding how communities function. Estimates of secondary production for key species such as mysids are scarce, especially in estuarine environments. There are no estimates for mysid production in intermittently closed estuaries in the world, and no estimates for endemic New Zealand mysids. The current study presents length–mass models for two mysid species (Tenagomysis chiltoni Tattersall, 1923 and T. novae-zealandiae Thomson, 1900) from the south-eastern coast of the South Island, New Zealand. Kaikorai Lagoon, a small intermittently closed estuary, supported a large average annual biomass of T. novae-zealandiae (861.77 mg m–2) and T. chiltoni (971.90 mg m–2). The Hynes average-cohort method was used with length–mass models to estimate the annual production of breeding populations of T. chiltoni and T. novae-zealandiae collected over a year in parts of the Kaikorai Lagoon. Compared with similar temperate ecosystems worldwide, the studied ecosystem indicated high annual production (11 328.8 mg m–2 year–1 and 6585.2 mg m–2 year–1) and turnover rates (P : B) (13.16 and 6.78) for T. novae-zealandiae and T. chiltoni, respectively. High annual secondary production may be due to relatively stable hydrological and food conditions found in intermittently closed estuaries, leading to dense stable populations that are maintained through much of the year.

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6

Plew, David R., John R. Zeldis, Bruce D. Dudley, Amy L. Whitehead, Leigh M. Stevens, Barry M. Robertson, and Ben P. Robertson. "Assessing the Eutrophic Susceptibility of New Zealand Estuaries." Estuaries and Coasts 43, no. 8 (April 28, 2020): 2015–33. http://dx.doi.org/10.1007/s12237-020-00729-w.

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Abstract We developed a method to predict the susceptibility of New Zealand estuaries to eutrophication. This method predicts macroalgae and phytoplankton responses to potential nutrient concentrations and flushing times, obtained nationally from simple dilution models, a GIS land-use model and physical estuary properties. Macroalgal response was based on an empirically derived relationship between potential nitrogen concentrations and an established macroalgal index (EQR) and phytoplankton response using an analytical growth model. Intertidal area was used to determine which primary producer was likely to lead to eutrophic conditions within estuaries. We calculated the eutrophication susceptibility of 399 New Zealand estuaries and assigned them to susceptibility bands A (lowest expected impact) to D (highest expected impact). Twenty-seven percent of New Zealand estuaries have high or very high eutrophication susceptibilities (band C or D), mostly (63% of band C and D) due to macroalgae. The physical properties of estuaries strongly influence susceptibility to macroalgae or phytoplankton blooms, and estuaries with similar physical properties cluster spatially around New Zealand’s coasts. As a result, regional patterns in susceptibility are apparent due to a combination of estuary types and land use patterns. The few areas in New Zealand with consistently low estuary eutrophication susceptibilities are either undeveloped or have estuaries with short flushing times, low intertidal area and/or minimal tidal influx. Estuaries with conditions favourable for macroalgae are most at risk. Our approach provides estuary-integrated susceptibility scores likely to be of use as a regional or national screening tool to prioritise more in-depth estuary assessments, to evaluate likely responses to altered nutrient loading regimes and assist in developing management strategies for estuaries.

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7

Smith, Quentin H. T., Andrew D. Heap*, and Scott L. Nichol. "Origin and Formation of an Estuarine Barrier Island, Tapora Island, New Zealand." Journal of Coastal Research 262 (March 2010): 292–300. http://dx.doi.org/10.2112/08-1127.1.

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8

Hemmingsen, Maree A. "Radiocarbon age for estuarine shells from Lakelands, Lake Ellesmere (Te Waihora), New Zealand." New Zealand Journal of Marine and Freshwater Research 35, no. 2 (June 2001): 329–34. http://dx.doi.org/10.1080/00288330.2001.9517003.

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9

Coleman, M. A., J. S. Clark, M. A. Doblin, M. J. Bishop, and B. P. Kelaher. "Genetic differentiation between estuarine and open coast ecotypes of a dominant ecosystem engineer." Marine and Freshwater Research 70, no. 7 (2019): 977. http://dx.doi.org/10.1071/mf17392.

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Temperate intertidal shores globally are often dominated by habitat-forming seaweeds, but our knowledge of these systems is heavily biased towards northern hemisphere species. Rocky intertidal shores throughout Australia and New Zealand are dominated by a single monotypic species, Hormosira banksii. This species plays a key role in facilitating biodiversity on both rocky shores and estuarine habitats, yet we know little about the processes that structure populations. Herein we characterise the genetic diversity and structure of Hormosira and demonstrate strong restrictions to gene flow over small spatial scales, as well as between estuarine and open coast populations. Estuarine ecotypes were often genetically unique from nearby open coast populations, possibly due to extant reduced gene flow between habitats, founder effects and coastal geomorphology. Deviations from random mating in many locations suggest complex demographic processes are at play within shores, including clonality in estuarine populations. Strong isolation by distance in Hormosira suggests that spatial management of intertidal habitats will necessitate a network of broad-scale protection. Understanding patterns of genetic diversity and gene flow in this important ecosystem engineer will enhance the ability to manage, conserve and restore this key species into the future.

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10

Alfaro, Andrea C. "Effects of mangrove removal on benthic communities and sediment characteristics at Mangawhai Harbour, northern New Zealand." ICES Journal of Marine Science 67, no. 6 (May 18, 2010): 1087–104. http://dx.doi.org/10.1093/icesjms/fsq034.

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Abstract Alfaro, A. C. 2010. Effects of mangrove removal on benthic communities and sediment characteristics at Mangawhai Harbour, northern New Zealand. – ICES Journal of Marine Science, 67: 1087–1104. The spread of mangroves at many locations in temperate northern New Zealand provides a stark contrast to the well-documented trend in mangrove forest decline recorded through the tropics and subtropics. To explore this difference, improved understanding is needed of New Zealand's mangrove ecosystems and how they respond to anthropogenic disturbance. The effect of mangrove removal on the community ecology of mangrove stands and adjacent habitats was investigated within Mangawhai Estuary, northern New Zealand, between March 2004 and September 2006. The vegetation, benthic macrofauna, and sediments were sampled within habitats (marshgrass, mangrove stands, pneumatophore zones, sandflats, and channels) at a treatment site (mangroves removed) and two undisturbed sites, before and after mangrove-removal activities. Mature mangrove habitats had less total abundance and fewer taxa than all the other habitats sampled and were dominated by pulmonate snails (Amphibola crenata) and mud crabs (Helice crassa). Whereas faunal composition varied seasonally as a result of life-history dynamics, temporal changes could be attributed to mangrove-removal activities. Mangrove eradication was followed by immediate changes in the sediment from a muddy to sandier environment, which favoured an overall increase in the abundance of crabs, snails, and bivalves. However, unexpected topographic catchment reconfigurations in late 2005 may have caused a subsequent increase in the delivery of silt and organic content to the study area and an overall decrease in faunal density in March and September 2006. The study provides direct evidence of the effect of mangroves on sediment and benthic faunal characteristics and the importance of catchment-derived imports to estuarine ecosystems.

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11

Stevens, CL, and MJ Smith. "Turbulent mixing in a stratified estuarine tidal channel: Hikapu Reach, Pelorus Sound, New Zealand." New Zealand Journal of Marine and Freshwater Research 50, no. 4 (May 17, 2016): 485–505. http://dx.doi.org/10.1080/00288330.2016.1171243.

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12

Stevens, Craig L. "Turbulence in an estuarine embayment: Observations from Beatrix Bay, New Zealand." Journal of Geophysical Research: Oceans 108, no. C2 (February 2003): n/a. http://dx.doi.org/10.1029/2001jc001221.

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13

Bell, Robert G. "Behaviour of dissolved silica, and estuarine/coastal mixing and exchange processes at Tairua Harbour, New Zealand." New Zealand Journal of Marine and Freshwater Research 28, no. 1 (March 1994): 55–68. http://dx.doi.org/10.1080/00288330.1994.9516596.

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14

Conran, John G., Raymond J. Carpenter, and Gregory J. Jordan. "Early Eocene Ripogonum (Liliales: Ripogonaceae) leaf macrofossils from southern Australia." Australian Systematic Botany 22, no. 3 (2009): 219. http://dx.doi.org/10.1071/sb08050.

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We present evidence that fossil leaves from an early Eocene estuarine mudstone deposit at Lowana Road in western Tasmania include the oldest records of the extant monocot genus, Ripogonum (Ripogonaceae). These fossils are similar to the extant eastern Australian and Papua New Guinean R. album R.Br. and New Zealand R. scandens J.R. et G.Forst., and are described as a new species, R. tasmanicum Conran, R.J.Carp. & G.J.Jord. The venation, cuticular and other leaf features of this fossil are included in a morphology-based phylogenetic analysis for the genus, and character evolution is discussed in relation to the ecology of the extant species and the palaeoenvironments of known Ripogonaceae fossil sites. The fossil (albeit on leaf characters) was placed close to the base of a black-fruited, Australian endemic Ripogonum clade. This suggests that the family have a long and conservative evolutionary history in association with moist forests, with the fossil locality showing palaeoclimate similar to the environments that most Ripogonum species still occupy today.

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15

Clark, DE, F. Stephenson, JE Hewitt, JI Ellis, A. Zaiko, A. Berthelsen, RH Bulmer, and CA Pilditch. "Influence of land-derived stressors and environmental variability on compositional turnover and diversity of estuarine benthic communities." Marine Ecology Progress Series 666 (May 20, 2021): 1–18. http://dx.doi.org/10.3354/meps13714.

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It can be challenging to differentiate community changes caused by human activities from the influence of natural background variability. Using gradient forest analysis, we explored the relative importance of environmental factors, operating across multiple spatio-temporal scales, in influencing patterns of compositional turnover in estuarine benthic macroinvertebrate communities across New Zealand. Both land-derived stressors (represented by sediment mud content and total sediment nitrogen and phosphorus content) and natural environmental variables (represented by sea surface temperature, Southern Oscillation Index, and wind-wave exposure) were important predictors of compositional turnover, reflecting a matrix of processes interacting across space and time. Generalized linear models were used to determine whether measures of benthic macroinvertebrate diversity, which are commonly used as indicators of ecological health on a local scale, changed in a way that was consistent with the compositional turnover along the environmental gradient. As expected, compositional turnover along land-derived stressor gradients was negatively associated with diversity indices, suggesting a decline in ecological health as land-derived stressors increase. This study moves towards an ecosystem-based management approach that focusses on cumulative effects rather than single stressors by considering how multiple land-derived stressors influence indicators of estuarine health, against a background of natural variability across several spatio-temporal scales.

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16

Turner, S. J. "Growth and productivity of intertidalZostera capricorniin New Zealand estuaries." New Zealand Journal of Marine and Freshwater Research 41, no. 1 (March 2007): 77–90. http://dx.doi.org/10.1080/00288330709509897.

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17

Bulmer, R. H., C. J. Lundquist, and L. Schwendenmann. "Sediment properties and CO2 efflux from intact and cleared temperate mangrove forests." Biogeosciences 12, no. 20 (October 28, 2015): 6169–80. http://dx.doi.org/10.5194/bg-12-6169-2015.

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Abstract. Temperate mangrove forests in New Zealand have increased in area over recent decades. Expansion of temperate mangroves in New Zealand is associated with perceived loss of other estuarine habitats, and decreased recreational and amenity values, resulting in clearing of mangrove forests. In the tropics, changes in sediment characteristics and carbon efflux have been reported following mangrove clearance. This is the first study in temperate mangrove (Avicennia marina) forests investigating the impact of clearing on sediment CO2 efflux and associated biotic and abiotic factors. Sediment CO2 efflux rates from intact (168.5 ± 45.8 mmol m−2 d−1) and cleared (133.9 ± 37.2 mmol m−2 d−1) mangrove forests in New Zealand are comparable to rates measured in tropical mangrove forests. We did not find a significant difference in sediment CO2 efflux rates between intact and cleared temperate mangrove forests. Pre-shading the sediment for more than 30 min prior to dark chamber measurements was found to have no significant effect on sediment CO2 efflux. This suggests that the continuation of photosynthetic CO2 uptake by biofilm communities was not occurring after placement of dark chambers. Rather, above-ground mangrove biomass, sediment temperature and chlorophyll a concentration were the main factors explaining the variability in sediment CO2 efflux in intact mangrove forests. The main factors influencing sediment CO2 efflux in cleared mangrove forest sites were sediment organic carbon concentration, nitrogen concentration and sediment grain size. Our results show that greater consideration should be given regarding the rate of carbon released from mangrove forest following clearance and the relative contribution to global carbon emissions.

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18

Brenneis, Valance E. F., Andrew Sih, and Catherine E. de Rivera. "Integration of an invasive consumer into an estuarine food web: direct and indirect effects of the New Zealand mud snail." Oecologia 167, no. 1 (March 30, 2011): 169–79. http://dx.doi.org/10.1007/s00442-011-1962-8.

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19

Heggie, Keira, and Candida Savage. "Nitrogen yields from New Zealand coastal catchments to receiving estuaries." New Zealand Journal of Marine and Freshwater Research 43, no. 5 (December 2009): 1039–52. http://dx.doi.org/10.1080/00288330.2009.9626527.

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20

Siciliano, Alfonso, David R. Schiel, and Mads S. Thomsen. "Effects of local anthropogenic stressors on a habitat cascade in an estuarine seagrass system." Marine and Freshwater Research 70, no. 8 (2019): 1129. http://dx.doi.org/10.1071/mf18414.

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Recent research has shown that co-occurring primary and secondary habitat-forming species typically support higher biodiversity than do monocultures of the primary habitat-former alone. However, these ‘habitat cascades’ may not be universal and it is important to know whether, when and where positive effects on biodiversity from secondary habitat-forming species change to negative effects. Here, we tested how anthropogenic stressors (fertilisation and sedimentation) and unattached secondary habitat-forming Ulva seaweeds affected the primary habitat-forming seagrass, Zostera muelleri, and its associated invertebrates in the Avon–Heathcote Estuary, New Zealand. We experimentally stressed Zostera by adding different fertilisation and sediment levels. Fertilisation had little impact, whereas even low sedimentation levels had strong negative effects on Zostera and its associated fauna. In a second experiment, sediments and Ulva were added to seagrass beds and unvegetated mudflats to test whether sediment stress modifies habitat cascades. We found again strong negative effects of sediments on Zostera, irrespective of spatio-temporal conditions, and that negative effects of sediments on invertebrates were enhanced in the presence of the secondary habitat former. These results highlighted that anthropogenic stressors can destabilise habitat cascades; processes that may be of particular importance in estuaries that are characterised by low biodiversity and stressful environmental conditions.

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21

Ross, Philip M., Ian D. Hogg, Conrad A. Pilditch, Carolyn J. Lundquist, and Richard J. Wilkins. "Population Genetic Structure of the New Zealand Estuarine Clam Austrovenus stutchburyi (Bivalvia: Veneridae) Reveals Population Subdivision and Partial Congruence with Biogeographic Boundaries." Estuaries and Coasts 35, no. 1 (August 10, 2011): 143–54. http://dx.doi.org/10.1007/s12237-011-9429-z.

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22

Jahan, Sayka, and Vladimir Strezov. "Effect of shipping on the distribution of trace elements and petroleum hydrocarbons in the coastal basins of Australia: a review." Marine and Freshwater Research 71, no. 7 (2020): 794. http://dx.doi.org/10.1071/mf19031.

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This study surveyed levels of trace elements and hydrocarbon contamination in Australian seaport environments. Different activities contribute to discharges of trace elements and hydrocarbons into estuarine and marine environments. The elements of highest concern are As, Cu, Pb, Zn and Ni at Port Derwent, with Cd, Zn, Cu and Pb at Port Kembla and Zn and Cu at Botany Bay all exceeding the Australia and New Zealand Environment Conservation Council standards. Concentrations of some elements (Zn, Pb and Cu) in sediments at Port Kembla, Port Newcastle and the Derwent estuary are also higher than the Inter Sediment Quality Guidelines. The concentrations of polychlorinated biphenyls, dichlorodiphenyltrichloroethane and chlordane in the aquatic biota at two eastern ports (Port Jackson, Port Brisbane) are also among the highest in Australia and similar areas around the world. These findings provide baseline information on which to prioritise further research and formulate strategies to improve water quality in Australian port environments.

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23

BROOK, FRED J., MARTYN KENNEDY, TANIA M. KING, JOHNATHON RIDDEN, MATTHEW D. SHAW, and HAMISH G. SPENCER. "Catalogue of New Zealand land, freshwater and estuarine molluscan taxa named by Frederick Wollaston Hutton between 1879 and 1904." Zootaxa 4865, no. 1 (October 22, 2020): 1–73. http://dx.doi.org/10.11646/zootaxa.4865.1.1.

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Details are provided on 16 land snail genera, eight freshwater molluscan species, one estuarine species, 47 land snail species and varieties from New Zealand, and a further three land snail species putatively from New Zealand, which were described by Frederick Wollaston Hutton between 1879 and 1904. Original primary type material of 54 species was located during the present study. Lectotypes are designated for: Amphidoxa cornea Hutton, 1882, Amphidoxa jacquenetta Hutton, 1883, Amphidoxa perdita Hutton, 1883, Charopa cassandra Hutton, 1883, Cyclotus charmian Hutton, 1883, Fruticicola adriana Hutton, 1883, Gerontia cordelia Hutton, 1883, Gerontia pantherina Hutton, 1882, Microphysa pumila Hutton, 1882, Patula jessica Hutton, 1883, Patula lucetta Hutton, 1884, Patula sylvia Hutton, 1883, Patula tapirina Hutton, 1882, Pfeifferia cressida Hutton, 1883, Phrixgnathus celia Hutton, 1883, Phrixgnathus haasti Hutton, 1883, Phrixgnathus marginatus Hutton, 1882, Phrixgnathus phrynia Hutton, 1883, Rhytida australis Hutton, 1882, Strobila leiodon Hutton, 1882, Thalassia propinqua Hutton, 1882, Therasia thaisa Hutton, 1883, Therasia valeria Hutton, 1883 and Zonites helmsii Hutton, 1882. A neotype is designated for Rhytida citrina Hutton, 1882. Primary type material of the following taxa is figured herein for the first time: Amphidoxa lavinia Hutton, 1883, Cyclotus charmian Hutton, 1883, Fruticicola adriana Hutton, 1883, Leptopoma pannosa Hutton, 1882, Patula lucetta Hutton, 1884, Patula sylvia Hutton, 1883, Patula tapirina Hutton, 1882, Phacussa helmsi var. maculata Hutton, 1884, Phrixgnathus ariel Hutton, 1883, Phrixgnathus celia Hutton, 1883, Rhytida australis Hutton, 1882, Rissoa vana Hutton, 1873, Testacella vagans Hutton, 1882, Trochomorpha hermia Hutton, 1883 and Zonites helmsii Hutton, 1882. New taxonomic combinations introduced herein include Phacussa lucetta (Hutton, 1884) and Therasia propinqua (Hutton, 1882). Amphidoxa lavinia Hutton, 1883, Charopa cassandra Hutton, 1883, Patula timandra Hutton, 1883 and Trochomorpha hermia Hutton, 1883 are treated as junior synonyms of Tasmaphena sinclairii (Pfeiffer, 1846), Phacussa fulminata (Hutton, 1882), Fectola infecta (Reeve, 1852) and Advena campbellii (Gray, 1834), respectively.

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24

Paul, Sourav, Martin Krkosek, P. Keith Probert, and Gerard P. Closs. "Osmoregulation and survival of two mysid species of Tenagomysis in southern estuaries of New Zealand." Marine and Freshwater Research 64, no. 4 (2013): 340. http://dx.doi.org/10.1071/mf12316.

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The mysid shrimps Tenagomysis chiltoni and T. novaezealandiae are abundant in southern New Zealand estuaries; however, little is known of their osmoregulatory capacity and survival. We investigated their osmoregulation and survival under salinities of 0, 5, 10, 15, 20, 25, 30 and 33 at 5°C and 20°C, to evaluate if the variation in salinity limits their distribution in estuaries. T. chiltoni and T. novaezealandiae maintained species-specific haemolymph concentrations across the salinities tested. According to AIC model selection statistics, for osmoregulatory capacity, the combined effects of salinity and temperature emerged as the most parsimonious. For survival, the non-linear effect of salinity was found as the most supported model given the data. Mortality of T. chiltoni and T. novaezealandiae increased towards the extremes of fresh and salt water but was lower in intermediate salinities (10–25). The ability of these species to osmoregulate and survive were limited at 5°C, but improved at 20°C. Life-history stage was found to be critical for explaining the variations in survival. We concluded that salinity could influence osmoregulation and survival of Tenagomysis spp., and when interacting with temperature and life-history stage, may partly explain why both shrimp species could be found in intermediate salinities and why T. chiltoni is more prevalent in the upper reaches of southern New Zealand estuaries.

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Fisher, Thomas R., Rebecca J. Fox, Anne B. Gustafson, Erika Koontz, Michelle Lepori-Bui, and James Lewis. "Localized Water Quality Improvement in the Choptank Estuary, a Tributary of Chesapeake Bay." Estuaries and Coasts 44, no. 5 (January 13, 2021): 1274–93. http://dx.doi.org/10.1007/s12237-020-00872-4.

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AbstractChesapeake Bay has a long history of nutrient pollution resulting in degraded water quality. However, we report improvements in chlorophyll a in surface waters and dissolved oxygen in bottom waters at one of three estuarine stations in the Choptank tributary of Chesapeake Bay. We updated a previous nutrient budget for the estuary constructed for reference year 1998 using rates of atmospheric deposition, inputs of watershed diffuse sources (primarily agriculture), and discharges of point sources (primarily human waste) for reference year 2017. Parallel trends suggest that improvements in water quality at the one station were likely due to 20% reductions in direct atmospheric deposition on the estuary’s surface and 78–95% reductions in wastewater N and P due to installation of tertiary treatment. The agricultural sector, the dominant source of N and P, appeared to provide little contribution to improved water quality during this period. Although efforts to reduce nutrient losses from agriculture are common throughout the Choptank basin, widespread reductions from agricultural diffuse sources could make large contributions to improved water quality at all stations in the estuary. The response in the Choptank is similar to those observed elsewhere in the USA, Europe, Australia, and New Zealand due to improved wastewater treatment. Similar to our findings, the upper Potomac River of Chesapeake Bay saw improvements driven by reductions in atmospheric deposition. Unfortunately, few studies elsewhere have shown improvements in water quality due to agricultural management. The data presented here indicate that public and industrial investments in reductions of atmospheric emissions and upgrades to wastewater treatment plants have improved estuarine water quality in the Choptank.

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Brenneis, Valance E. F., Andrew Sih, and Catherine E. De Rivera. "Coexistence in the intertidal: interactions between the non-indigenous New Zealand mud snail Potamopyrgus antipodarum and the native estuarine isopod Gnorimosphaeroma insulare." Oikos 119, no. 11 (June 10, 2010): 1755–64. http://dx.doi.org/10.1111/j.1600-0706.2010.18471.x.

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27

Dudley, Bruce D., Olivia R. Burge, David Plew, and John Zeldis. "Effects of agricultural and urban land cover on New Zealand’s estuarine water quality." New Zealand Journal of Marine and Freshwater Research 54, no. 3 (March 1, 2020): 372–92. http://dx.doi.org/10.1080/00288330.2020.1729819.

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28

Taddese, Fasil, and Gerard P. Closs. "Spatiotemporal ichthyofaunal dynamics in a permanently open estuary, Otago, New Zealand." Marine and Freshwater Research 71, no. 1 (2020): 107. http://dx.doi.org/10.1071/mf19034.

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Understanding the spatial and temporal dynamics of the fish-assemblage structure of estuaries is indispensable in conservation and habitat-improvement efforts. This study reports seasonal as well as spatial dynamics of fish diversity of the Waikouaiti Estuary and indicates the key physicochemical variables that influence the ichthyofauna of the estuary. Fish were collected from upper, middle and lower reaches of the Waikouaiti Estuary monthly for 1 year, by using a seine net. In total, 15 species and 4967 individuals were collected during the study period. Distinct differences in ichthyofaunal composition, driven by spatiotemporal environmental heterogeneity, were observed between the three reaches of the Waikouaiti Estuary. Fish abundance was higher in the middle reach where the water is turbid. Whereas fish species with diadromous life history occurred more frequently in the upper reach of the estuary, marine-migrants and marine-stragglers were abundant in the lower reach. The present study indicated that salinity and turbidity were the best predictors of fish species composition in the different reaches of the Waikouaiti Estuary.

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O’Connell-Milne, SA, SR Wing, SH Suanda, JA Udy, LM Durante, NH Salmond, and LC Wing. "Interactions between bivalve filter feeding and oceanographic forcing drive the fluxes of organic matter and nutrients at an estuarine-coastal interface." Marine Ecology Progress Series 655 (November 26, 2020): 29–42. http://dx.doi.org/10.3354/meps13522.

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Fluxes of nutrients and organic matter between estuaries and the open coast comprise an important component of ecosystem connectivity. Nevertheless, relatively little is known about how oceanographic processes, for example onshore retention of water in the coastal boundary layer, interact with major sinks for particulate organic matter such as bivalve filter feeding within inlets and estuaries. To investigate this interaction, total fluxes of water, nutrients (NH4, NOx and PO4) and chlorophyll a between Waitati Inlet on the wave-exposed coast of the South Island, New Zealand, and the coastal ocean were quantified over 40 tidal cycles. We found declines in total flux of phytoplankton and increases in flux of NH4 between flood and ebb tides. Net declines in phytoplankton biomass followed a Type II functional response curve, consistent with consumption by the large biomass of filter feeding bivalves within the inlet; however, an asymptote was not reached for the highest concentrations, indicating that feeding was likely limited by exposure time rather than concentration of food relative to biomass. An information-theoretic framework was then used to infer the most likely combination of environmental conditions influencing total fluxes of phytoplankton into the inlet. Onshore wind stress, wave transport and salinity explained 90% of the variation in flux of phytoplankton entering the inlet on flood tides. These results highlight the importance of the interaction between oceanographic forcing and bivalve filter feeding in modulating material dynamics and connectivity between estuaries and the coastal ocean.

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Berthelsen, A., J. Atalah, D. Clark, E. Goodwin, M. Patterson, and J. Sinner. "Relationships between biotic indices, multiple stressors and natural variability in New Zealand estuaries." Ecological Indicators 85 (February 2018): 634–43. http://dx.doi.org/10.1016/j.ecolind.2017.10.060.

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Winterbourn, Michael J. "Life history and ecology ofPotamopyrgus estuarinus(Gastropoda: Tateidae) in the tidal reaches of two New Zealand rivers." Molluscan Research 36, no. 2 (April 2, 2016): 112–18. http://dx.doi.org/10.1080/13235818.2015.1128585.

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Paul, S., DM May, M. Lee, and GP Closs. "Body and brood sizes ofTenagomysisspp. (Crustacea: Mysida) in southern estuaries in New Zealand." New Zealand Journal of Marine and Freshwater Research 50, no. 3 (July 2, 2016): 433–43. http://dx.doi.org/10.1080/00288330.2016.1154077.

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Gongol, C., and C. Savage. "Spatial variation in rates of benthic denitrification and environmental controls in four New Zealand estuaries." Marine Ecology Progress Series 556 (September 8, 2016): 59–77. http://dx.doi.org/10.3354/meps11865.

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Weeks, Emily S., Russell G. Death, Kyleisha Foote, Rosalynn Anderson-Lederer, Michael K. Joy, and Paul Boyce. "Conservation Science Statement. The demise of New Zealand's freshwater flora and fauna: a forgotten treasure." Pacific Conservation Biology 22, no. 2 (2016): 110. http://dx.doi.org/10.1071/pc15038.

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New Zealand’s freshwater ecosystems support a diverse and unique array of endemic flora and fauna. However, the conservation of its freshwater biodiversity is often overlooked in comparison to terrestrial and marine environments, and is under increasing threat from agricultural intensification, urbanisation, climate change, invasive species, and water abstraction. New Zealand has some of the highest levels of threatened freshwater species in the world with, for example, up to 74% of native freshwater fish listed as endangered or at risk. Threatened species are often discounted in water policy and management that is predominantly focussed on balancing water quality and economic development rather than biodiversity. We identify six clear actions to redress the balance of protecting New Zealand’s freshwater biodiversity: 1. change legislation to adequately protect native and endemic fish species and invertebrates, including those harvested commercially and recreationally; 2. protect habitat critical to the survival of New Zealand’s rare and range-restricted fish, invertebrate and plant freshwater species; 3. include river habitat to protect ecosystem health in the National Objectives Framework for the National Policy Statement for freshwater; 4. establish monitoring and recovery plans for New Zealand’s threatened freshwater invertebrate fauna; 5. develop policy and best management practices for freshwater catchments in addition to lakes and rivers to also include wetlands, estuaries, and groundwater ecosystems; and 6. establish, improve, and maintain appropriately wide riparian zones that connect across entire water catchments. We have published these recommendations as a scientific statement prepared for the Oceania Section of the Society for Conservation Biology to facilitate communication of our thoughts to as wide an audience as possible (https://conbio.org/images/content_groups/Oceania/Scientific_Statement_1_.pdf, accessed 8 February 2016).

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KNOX, MATTHEW A., IAN D. HOGG, and CONRAD A. PILDITCH. "The role of vicariance and dispersal on New Zealand's estuarine biodiversity: the case of Paracorophium (Crustacea: Amphipoda)." Biological Journal of the Linnean Society 103, no. 4 (July 5, 2011): 863–74. http://dx.doi.org/10.1111/j.1095-8312.2011.01675.x.

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Schüller, Susanne E., Thomas S. Bianchi, Xinxin Li, Mead A. Allison, and Candida Savage. "Historical Reconstruction of Phytoplankton Composition in Estuaries of Fiordland, New Zealand: the Application of Plant Pigment Biomarkers." Estuaries and Coasts 38, no. 1 (February 1, 2014): 56–71. http://dx.doi.org/10.1007/s12237-014-9771-z.

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POORE, GARY C. B., F. RAMÍREZ, and A. SCHIARITI. "A new species of Chaetiliidae (Crustacea: Isopoda: Valvifera) from the Río de la Plata estuary, Argentina-Uruguay, and reconsideration of Macrochiridothea and Chiriscus." Zootaxa 2119, no. 1 (May 27, 2009): 51–65. http://dx.doi.org/10.11646/zootaxa.2119.1.4.

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A new species, Macrochiridothea estuariae, is described from the estuary of the Río de la Plata. It differs from other species of the genus in having weakly defined incisions on the side of the head. The genus Chiriscus Richardson, 1911, previously synonymised with Macrochiridothea Ohlin, 1901 is revived on the basis of a lobed article 4 on antenna 2 and a longer pereonite 7 to include the type species, Chiriscus australis Richardson, 1911, and C. giambiagiae (Torti & Bastida, 1972) transferred from Macrochiridothea. Nine other species of Macrochiridothea from southern South America and another from New Zealand are briefly diagnosed. A key is provided.

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Kennedy, David M., Beth V. Risdon, and Josephine LD Woods. "Holocene sea-level change and estuary infill in North West Nelson, central New Zealand." Holocene 32, no. 3 (November 21, 2021): 113–26. http://dx.doi.org/10.1177/09596836211060489.

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The sedimentary sequences found within estuaries in the north west Nelson region of central New Zealand are investigated in order to quantify the timing of the end of the Post Glacial Marine Transgression. This region has been identified as being relatively stable in terms of vertical tectonic movement during the Holocene, but is yet to yield any reconstructions of eustatic sea level. In this study, we investigate the Holocene infill of a barrier estuary (Parapara Inlet) through sedimentological analysis and radiocarbon dating of 18 vibracores up to 4.2 m in length. It is found that the estuary infilled through a combination of lateral flood tide and fluvial delta progradation as well as vertical central basin infill. The central basin infilled at a consistent rate of 0.4 mm/year in both the mid (7.0–6.0 ka) and late-Holocene (2.5–1.5 ka). By the time of early human (Maori) settlement (c. 1 ka), the estuary surface was at low intertidal elevations with sediment being transported from the fluvial to tidal delta. A discernible change in sedimentation rates could not be associated with Maori settlement; however, infill rates increased to at least 12.5 mm/year in the past 150 years due hydraulic sluicing associated with mining. The sedimentary history of Parapara Inlet is compared to nearby Whanganui Inlet, d’Urville Island and Nelson to establish the character of regional Holocene sea level movement. It is found that relative sea level reached modern elevations between 8 and 7 ka in the region. The similarity between sea level curves for the end of the post glacial marine transgression (PMT) to other tectonically stable sites in northern New Zealand suggests that this curve can now be considered a true eustatic signal for the New Zealand archipelago.

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Curtis, Thomas D., and Jeffrey S. Shima. "Geographic and sex‐specific variation in growth of yellow‐eyed mullet,Aldrichetta forsteri,from estuaries around New Zealand." New Zealand Journal of Marine and Freshwater Research 39, no. 6 (December 2005): 1277–85. http://dx.doi.org/10.1080/00288330.2005.9517392.

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Unwin, M. J., and G. J. Glova. "Changes in life history parameters in a naturally spawning population of chinook salmon (Oncorhynchus tshawytscha) associated with releases of hatchery-reared fish." Canadian Journal of Fisheries and Aquatic Sciences 54, no. 6 (June 1, 1997): 1235–45. http://dx.doi.org/10.1139/f97-031.

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Chinook salmon (Oncorhynchus tshawytscha) spawning runs in Glenariffe Stream, New Zealand, exhibited significant changes in life history traits following supplementation releases of hatchery-reared juveniles. Total run strength did not change but the proportion of naturally produced fish declined to 34%. Attempts to separate spawners of natural and hatchery origin were unsuccessful, and 31-48% of natural spawners are now of hatchery origin. Hatchery males were smaller at age 2 and 3 than males of natural origin, and more often matured as jacks, producing an 86-mm decrease in mean fork length over 28 years. There was no change in length at age or age at maturity for female spawners. The proportion of jacks entering Glenariffe Stream each year was positively correlated with the proportion of jacks in the ensuing cohort. Most differences between fish of natural and hatchery origin were related to hatchery rearing practices, but the decline in age at maturity among naturally produced males appears to reflect traits inherited from parent stock of hatchery origin. Hatchery releases may also favour the survival of ocean-type fry over stream-type fry, possibly reversing a tendency for stream-type behaviour to evolve in response to the lack of estuaries on most New Zealand chinook salmon rivers.

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Bulmer, R. H., L. Schwendenmann, and C. J. Lundquist. "Sediment CO2 efflux from cleared and intact temperate mangroves and tidal flats." Biogeosciences Discussions 12, no. 4 (February 25, 2015): 3547–76. http://dx.doi.org/10.5194/bgd-12-3547-2015.

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Abstract. Temperate mangroves in Southern Australia and New Zealand have been increasing in area over the past 50 years, whereas tropical mangroves have declined by 30–50% over a similar time frame. Tropical mangroves are understood to be an important carbon sink and carbon dioxide (CO2) emissions following clearance are estimated to be comparable or greater than CO2 emissions following the clearance of many terrestrial forest systems. Recreational and amenity values or perceived loss of other estuarine habitats due to expanding temperate mangrove forests have resulted in clearing of temperate mangroves. In this study, we investigated the impact of temperate mangrove clearance on CO2 efflux from the sediment to the atmosphere along with a range of other biotic and abiotic factors. Significantly higher CO2 efflux rates were measured in cleared (1.34 ± 0.46 μmol m2 s-1) and intact mangrove sites (2.31 ± 0.72 μmol m2 s-1) than in tidal flats (-0.23 ± 0.27 μmol m2 s-1). Site and sediment characteristics such as sediment carbon and nitrogen concentration, chlorophyll α concentration, grain size, mangrove height, macrofaunal abundance, sediment temperature and moisture were strongly correlated with sediment CO2 efflux. Our results suggest that carbon stored within temperate mangrove sediment is released over a period of years to decades after mangrove clearance. CO2 efflux from intact and cleared temperate mangroves was found to be comparable to rates observed in the tropics. Disturbance of the surface biofilm resulted in elevated CO2 efflux across all habitats, suggesting the important role of surface biofilm communities in mediating CO2 efflux.

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Mangan, S., KR Bryan, SF Thrush, RV Gladstone-Gallagher, AM Lohrer, and CA Pilditch. "Shady business: the darkening of estuaries constrains benthic ecosystem function." Marine Ecology Progress Series 647 (August 13, 2020): 33–48. http://dx.doi.org/10.3354/meps13410.

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Coastal intertidal soft-sediment habitats provide ecosystem services to millions of people worldwide, yet are under intense pressure from land-use change and sea-level rise (SLR). Both pressures interact to reduce light reaching the seafloor, thereby disrupting benthic primary producers and the ecosystem functions and services they provide. This study considers the implications of altered light climate on microphytobenthic (MPB) production in shallow estuaries. Continuous measurements of seafloor photosynthetically active radiation (PAR) were made over 9 mo on intertidal sandflats in 14 New Zealand estuaries spanning a turbidity gradient. A literature summary of benthic photosynthesis-irradiance curves was used to predict PAR limitation at sampling sites. Estimates of the proportion of time MPB would be light limited during emersion ranged from a median of 32-64% compared to a median of 55-100% during immersion. For estuaries close to 100% PAR limitation during immersion, emerged intertidal areas represent a refuge for MPB production which is vulnerable to SLR. Based on hypsometric curves (a representation of estuary bathymetry), the intertidal area of our study estuaries is predicted to decrease by 27-94% in response to SLR of 1.4 m. The combination of high PAR limitation during immersion and large losses of intertidal area will increase vulnerability to the loss of MPB production and the associated ecosystem services, which will push these ecosystems towards tipping points. The research highlights how the interplay between local and global scale stressors may ultimately trigger ecological collapse under future global change.

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Kingsford, Richard T., and James E. M. Watson. "Climate Change in Oceania – A synthesis of biodiversity impacts and adaptations." Pacific Conservation Biology 17, no. 3 (2011): 270. http://dx.doi.org/10.1071/pc110270.

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Climate change is already affecting many of the world’s ecosystems with far-reaching impacts. In this special issue, contributors focus on the current and projected impacts of climate change across different geographical regions of Oceania (Australia, Pacific Islands and New Zealand). In this synthesis, we examine how climate change is affecting the three main realms: terrestrial, freshwater (broadly including estuarine and inland saline systems) and marine. Within this context, we also examine general strategies for climate adaptation including reducing other threats (e.g., habitat loss and degradation), expanding protected areas, increasing connectivity, restoring habitat and translocations. We show that many of these general strategies will not overcome all the threats caused by climate change and specific solutions are likely to be necessary. Beyond the implementation of these strategies, there are significant future challenges which will hamper effective adaptation that need to be overcome by the scientific community. Our current understanding of the impacts of climate change on biodiversity remains poor; this is particularly true for poor nations in the region. There is also considerable uncertainty in forecasts of climate change, particularly at the local scale, and this uncertainty impacts pro-active planning. This makes effective implementation particularly challenging. Considerable focus is needed into ecosystem-based adaptation where local communities are integrally involved, allied with more active and accountable management of conservation, through adaptive management processes. The world is experiencing far reaching and long-term changes to ecosystems with major impacts on human communities, particularly in relation to ecosystem services. Our ability to develop effective adaptation strategies from the broad scale policy (e.g., emissions control) to local scale management (e.g., building resilience in ecosystems) will be significantly tested but the world is in an important period and scientists and practitioners need to keep trying different approaches and reporting their successes and failures to the wider community.

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Bellais, Kaylyn C., Samuel T. Barber, Donald A. Beebe, and Murlene W. Clark. "Lake or Estuary? Sedimentary and Benthic Foraminiferal Characterization of a Gulf of Mexico Coastal Dune Lake." Gulf and Caribbean Research 31 (2020): SC46—SC52. http://dx.doi.org/10.18785/gcr.3101.18.

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Coastal dune lakes are shallow estuaries located within dune environments that share a permanent or intermittent connection with the sea. Because coastal dune lakes are found in few locations worldwide (e.g. Australia, New Zealand, Florida, etc.) they represent unique environments worthy of protection. However; there is a distinct lack of scientific data related to the function and ecology of coastal dune lakes, especially in the Gulf of Mexico. Therefore, the purpose of this study was to characterize the sedimentology and foraminifera of a representative coastal dune lake in Walton County, FL (i.e. Eastern Lake) and determine whether it shares geologic similarities with nearby estuaries. Ten Ekman sediment grab samples were collected along a transect spanning the length of Eastern Lake. The samples were processed to determine sedimentary properties and foraminiferal assemblages. Results from the sedimentary and foraminiferal analyses reveal 3 distinct depositional environments including: (1) a coarse grained, moderately well sorted, organic poor, sandy beach facies with both agglutinated and calcareous foraminifera, (2) a fine grained, very poorly sorted, organic rich central mud basin facies with mostly calcareous foraminifera, and (3) a coarse grained, poorly sorted, organic rich sandy marsh delta facies dominated by agglutinated foraminifera. These environments and foraminiferal patterns are also found in much larger nearby estuaries including Choctawhatchee Bay, Pensacola Bay, and Mobile Bay. Our results therefore suggest that coastal dune lakes may serve as down-scaled micro-estuaries and are functionally related to larger estuaries of the Gulf Coast despite their size.

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LAST, PETER R., and DANIEL C. GLEDHILL. "The Maugean Skate, Zearaja maugeana sp. nov. (Rajiformes: Rajidae) — a micro-endemic, Gondwanan relict from Tasmanian estuaries." Zootaxa 1494, no. 1 (May 31, 2007): 45–65. http://dx.doi.org/10.11646/zootaxa.1494.1.2.

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A new species of rajin skate, Zearaja maugeana sp. nov., is described on the basis of specimens from two estuaries in remote southwestern Tasmania. The species, known locally as the Maugean Skate, has been assessed as Endangered in the IUCN Red List of Threatened Animals based on its rarity and very narrow geographic range. It is also one of the few skates worldwide to occur mainly in brackish water. The Maugean Skate belongs to a group of anatomically conservative, Dipturus-like skates conforming to the currently unrecognized genus Zearaja Whitley. This ancient group, with a Gondwanan lineage possibly dating back to the Cretaceous, contains at least two other species: Z. nasuta from New Zealand and Z. chilensis from South America. The skeletal morphologies of the Zearaja species are compared with typical Dipturus skates and their phylogenetic position discussed.

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Francis, Malcolm P., David Harasti, and Hamish A. Malcolm. "Surviving under pressure and protection: a review of the biology, ecology and population status of the highly vulnerable grouper Epinephelus daemelii." Marine and Freshwater Research 67, no. 8 (2016): 1215. http://dx.doi.org/10.1071/mf15099.

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Epinephelus daemelii is a threatened serranid grouper species that is restricted to the south-western Pacific Ocean, ranging from eastern Australia to northern New Zealand and the Kermadec Islands. Declines in its abundance due to fishing pressure were reported as early as 1916. Aspects of this species’ biology and behaviour that make it vulnerable include its longevity, late age at maturity, protogynous hermaphroditism, territoriality and limited shallow reef habitat. Adults prefer complex habitat with caves and overhangs at depths of less than 50m, whereas juveniles live in rock pools, shallow intertidal reefs and estuaries. Epinephelus daemelii lives at least 65 years and reaches 170-cm total length. Individuals change sex from female to male at ~100–110cm and ~25 years. Absence of large (>100cm) fish across a large part of their range has implications for reproduction. Although nearly fully protected, incidental bycatch still occurs. A lack of long-term data hinders determination of population status, but abundance appears to be much lower than before, except in remote regions (Kermadec Islands, Elizabeth and Middleton reefs) with extensive no-fishing areas. Further prohibitions on fishing in key locations are likely to be important for the recovery and long-term survival of this species.

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Sim-Smith, Carina J., Andrew G. Jeffs, and Craig A. Radford. "Environmental influences on the larval recruitment dynamics of snapper, Chrysophrys auratus (Sparidae)." Marine and Freshwater Research 64, no. 8 (2013): 726. http://dx.doi.org/10.1071/mf12255.

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Recruitment success in demersal fish species that settle in estuaries after a pelagic larval duration in coastal waters is dependent on (1) abiotic and biotic variables that promote good survival, and (2) local environmental conditions that facilitate and direct the transport of larvae to settlement habitats. In the present study, we described the patterns of larval abundance, pelagic larval duration and settlement of a commercially important sparid, Chrysophrys auratus, in northern New Zealand over 2 years, and investigated the relationships among pelagic larval duration or daily settler abundance and various environmental variables. Pelagic larval duration varied from 17 to 33 days and the successful spawning period that produced settled juveniles varied from 29 to 109 days among our four sites. For 91% of fish captured, the average temperature during the pelagic larval duration was >18°C. Significant correlations between daily settler abundance and environmental variables varied among sites and between years; however, temperature, tidal range and on-shore winds were most strongly correlated with settlement, explaining up to 38% of the variability in settler abundance. The present results suggested that, in some locations, high water temperatures, large tides and on-shore winds are likely to increase recruitment success in C. auratus.

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Byun, Do-Seong, and Deirdre E. Hart. "A monthly tidal envelope classification for semidiurnal regimes in terms of the relative proportions of the S2, N2, and M2 constituents." Ocean Science 16, no. 4 (August 18, 2020): 965–77. http://dx.doi.org/10.5194/os-16-965-2020.

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Abstract. Daily tidal water level variations are a key control on shore ecology, on access to marine environments via ports, jetties, and wharves, on drainage links between the ocean and coastal hydrosystems such as lagoons and estuaries, and on the duration and frequency of opportunities to access the intertidal zone for recreation and food harvesting purposes. Further, high perigean spring tides interact with extreme weather events to produce significant coastal inundations in low-lying coastal settlements such as on deltas. Thus an understanding of daily through monthly tidal envelope characteristics is fundamental for resilient coastal management and development practices. For decades, scientists have described and compared daily tidal forms around the world's coasts based on the four main tidal amplitudes. Our paper builds on this “daily” method by adjusting the constituent analysis to distinguish between the different monthly types of tidal envelopes occurring in the semidiurnal coastal waters around New Zealand. Analyses of tidal records from 27 stations are used alongside data from the FES2014 tide model in order to find the key characteristics and constituent ratios of tides that can be used to classify monthly tidal envelopes. The resulting monthly tidal envelope classification approach described (E) is simple, complementary to the successful and much used daily tidal form factor (F), and of use for coastal flooding and maritime operation management and planning applications in areas with semidiurnal regimes.

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Hamilton, L. J. "Large mass strandings of selected odontocete species: statistics, locations, and relation to earth processes." J. Cetacean Res. Manage. 19, no. 1 (January 24, 2023): 57–78. http://dx.doi.org/10.47536/jcrm.v19i1.415.

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Larger mass strandings of open ocean odontocetes (toothed whales) of 10+ animals are examined with a compilation of 710 worldwide events. Sixspecies form 96% of events (false killer, long-finned pilot, melon-headed, short-finned pilot, sperm and white whales), with beaked, killer, andpygmy killer whales forming 4%. Site type was determined for 630 events – three-quarters (76%) are in bays, 14% in shallow topographicallycomplex areas (estuarine environments, straits, keys, reef and coastal lagoons), 8% on relatively unindented coasts, with ice entrapment (of killerwhales) and miscellaneous categories being 2%. For the 76% of events in bays, sites with headland-bay character make up 42%, spit-bays 20%(even though there are only four of them), indented bays 9% and unspecified bay types 5%. Headland-bays and spit-bays become stranding sitesthrough the properties endowed them by their mechanisms of formation and maintenance, but these mechanisms differ greatly for the two.Breakwaters, groyne series, tides, partial burial, and violent storms also appear as themes. Nearshore slopes are less than 1° for 94 of 105 siteshaving bathymetry information, with only two reaching or exceeding 3°. Some types of potential stranding sites can be identified by simplequantitative specifications for planform, sediment size, and seabed slope, although strandings will not necessarily occur there. There is an indicationthat larger strandings are globally correlated with areas of higher oceanic primary productivity near landmasses and oceanic islands, but quantitativestudies are needed to clarify any such possible relationship. There is also an indication that larger strandings are associated with plate tectonics,with few events being seen on the steeper swell resistant active western margins of South America and South Island (New Zealand) in particular.In contrast several larger events are recorded for the relatively older passive margins of the south-eastern sides of these two landmasses, putativelybecause waves and swell have had time to construct stranding sites on them. Similarly, few larger events are seen for steeper shores adjacent tocoastal highlands, such as those of South Africa and Brazil. These observations indicate previously unsuspected relations between the phenomenonof odontocete mass strandings and global scale earth and ocean processes, but they are essentially hypotheses in need of more quantitativeexamination.

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Brown, Lauren. "The enigmatic palaeoecology and palaeobiogeography of the giant, horned, fossil turtles of Australasia: a review and reanalysis of the data." Herpetological Journal, Volume 29, Number 4 (October 1, 2018): 252–63. http://dx.doi.org/10.33256/29.4.252263.

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The distribution pattern of the bizarre Australasian giant, horned, fossil turtles of the clade Meiolaniidae has puzzled biogeographers since their discovery late in the nineteenth century. While their distribution suggests a Gondwanan origin, the lack of fossil evidence from key times and places has inhibited a better understanding of their dispersal pathways to Australia and the south-west Pacific islands in which their fossils have been found. Much palaeoecological speculation related to their dispersal capabilities, ranging from purely terrestrial to freshwater, estuarine, and saltwater lifestyles, has been proposed to explain their enigmatic presence across a wide swath of Oceania. Various lines of fossil, anatomical and ecological evidence now strongly suggest a highly terrestrial lifestyle, and we believe these traits, reinforced by an abundance of marine predators and ever-widening saltwater gaps between land areas during the Late Mesozoic and Tertiary, minimise the importance of saltwater dispersal as an explanation for the observed meiolaniid distribution pattern. Here we propose that the fragmentation of Gondwana provided the main dispersal vehicle for the meiolaniids and that land connections were also used to access suitable habitats and expand their range. The recently recognised continent of Zealandia, along with Australia, South America, and probably Antarctica, transported all known meiolaniid turtles to their present locations. However, ice cover on Antarctica, and the nearly total submergence of Zealandia in essence preclude the current likelihood of fossil discovery in these critical locations. The islands of New Caledonia, Tiga (in the Loyalty Islands), Walpole, and Lord Howe served as refugia for Zealandia meiolaniids as the continent submerged.

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