Journal articles on the topic 'Alligator Creek'

Abstract The alligator snapping turtle Macrochelys temminckii is the largest freshwater turtle in North America and humans seek it as a food source, primarily in Louisiana. Scientists point to decades of intensive commercial harvest of alligator snapping turtles as a cause of population declines. The Louisiana Department of Wildlife and Fisheries initiated a head-start program for alligator snapping turtles and released 53 head-started juveniles at seven sites along an approximately 5.7-km stretch of Bundick Creek in southwest Louisiana between November 2015 and October 2016. Before release, department personnel measured, weighed, and marked all alligator snapping turtles with both an internal passive integrated transponder tag and a numbered external tag. In 2018, the U.S. Geological Survey initiated a turtle trapping survey at those seven release sites targeting the head-started alligator snapping turtles. In 1 wk of trapping effort at each site, we recorded 69 turtle captures comprising seven species, including 15 alligator snapping turtles (representing 12 individuals). Of those 12 individuals, 8 were head-started juveniles and 4 were native to the creek. A landowner captured an additional head-started juvenile alligator snapping turtle during our trapping and we took measurements before its release. A minimum of 17% of head-started alligator snapping turtles survived since release, and we trapped most captured head-started individuals near their release site; the captured individuals exhibited growth consistent with other studies, indicating acclimatization to their new environment. Three head-started alligator snapping turtles had their external tags entangled in the net mesh, and two of these turtles drowned. An additional two head-started individuals lost their external tags in the natural environment prior to their capture in this study. The Louisiana Department of Wildlife and Fisheries discontinued the use of external tags based on our findings, as these tags were detrimental to the health of head-started turtles.

The movements of fishes marked, released and recaptured during a fish trapping study in the estuary of Alligator Creek in tropical north-eastern Australia were studied over a period of two and a half years. The ability to place fish traps accurately with respect to landmarks enabled movements as short as 40 m to be detected. For each of six species of fish, more than 10 individuals were recaptured in Alligator Creek. Within these species, 258 of 1164 tagged fish were recaptured. Three patterns of movement were apparent. The serranids Epinephelus coioides and E. malabaricus and the lutjanid Lutjanus russelli tended to move little, usually being recaptured within 40 m of the site of release. The sparids Acanthopagrus australis and A. berda moved more extensively but still tended to remain within a few hundred metres for extended periods. All the above species demonstrated a strong tendency to be recaptured on the side of the creek on which they were initially captured. The tetraodontid Arothron manilensis proved to be much more vagile than did the other species, ranging freely over relatively large areas of the estuary and often crossing to the opposite bank of the creek. No species showed any preferred direction of movement or any tendency for increased displacement from the site of release with increased time at liberty.

Estuaries are areas known for biological diversity, and their soundscapes reflect the acoustic signals used by organisms to communicate, defend territories, reproduce, and forage in an environment that has limited visibility. These biological sounds may be rhythmic in nature, spatially heterogeneous, and can provide information on habitat quality. The goal of our study was to investigate the temporal and spatial variability of sounds in Chechessee Creek (Stns CC1 and CC2) and an adjacent saltwater impoundment (Great Salt Pond, GSP) in South Carolina, USA, from April to November 2016. Fixed recording platforms revealed that sound pressure levels (SPLs) were significantly higher in CC1 and CC2 compared to GSP. We detected some biological sounds in GSP (snapping shrimp genera Alpheus and Synalpheus, silver perch Bairdiella chrysoura, oyster toadfish Opsanus tau, spotted seatrout Cynoscion nebulosus, Atlantic croaker Micropogonias undulatus, and American alligator Alligator mississippiensis); however, biological sound was much more prevalent in CC1 and CC2. In Chechessee Creek, snapping shrimp, oyster toadfish, and spotted seatrout sounds followed distinct temporal rhythms. Using these data, we conducted spatial passive acoustic surveys in Chechessee Creek. We discovered elevated high frequency SPLs (representing snapping shrimp acoustic activity) near an anti-erosion wall, as well as increased low frequency SPLs (indicating spotted seatrout spawning aggregations) near the anti-erosion wall and at the mouth of Chechessee Creek. This study has demonstrated the utility of combining stationary and mobile recording platforms to detect acoustic hotspots of biological sounds.

Spatial and temporal patterns of distribution and abundance of large, demersal fishes in the deep-water sections of Alligator Creek, in tropical northern Australia, were investigated. Small Antillean Z-style fish traps were utilized to compare different estuarine habitats along the navigable length of the creek. In particular, the traps were used to target the structurally heterogeneous 'snag' habitats provided by areas of submerged mangrove prop roots and fallen timbers in the deeper areas of the estuary. During the study, 962 fish of 23 species from 15 families were trapped over 1128 trapping days, at an overall catch rate of 0.85 fish trap-1 day-1. Catches by numbers were dominated by two genera: Acanthopagrus (Sparidae) (51.8%) and Epinephelus (Serranidae) (20.3%). Of the 23 species trapped, eight had not been recorded during previous studies of Alligator Creek that used more conventional netting methods to target fishes in shallow parts of the estuary. In trap catches, the total number of fish, the number of species, and the numbers of individuals of the most common species showed a general decline towards the upper areas of the estuary and generally were higher in 'snag' habitats than in areas lacking such structures. No clear pattern of temporal differences during the study was detected. Angling and seine-net catch data were used as independent indicators of spatial patterns of distribution and abundance for comparison with the patterns obtained from the catch data of traps. Data from all three sources demonstrated similar spatial patterns.

Sediment fluxes and sinks based on total sediment load for Magela Creek in the Australian wet–dry tropics have been constructed from detailed measurements of stream suspended sediment (turbidity and suspended sand) and bed load for the 10-year period, 2001–2002 to 2010–2011. This work shows that the sediment trap efficiency of the vegetated wetlands on lower Magela is high at ~89.5%. Sediment fluxes are the lowest in the world because of low soil erosion rates and because upstream floodplains and downstream wetlands trap and store sediment. Bedload yields are less than suspended sediment yields, but the amount of silt and clay is much less than the amount of sand (suspended sand and bedload). All sand is stored upstream of the East Alligator River. Downstream connectivity of sediment movement does not occur. Therefore, sediment moves discontinuously from the upper to the lower catchment.

Cover of the alga Chara hornemannii Wallman and water-quality parameters were measured over a 3-year period in adjacent mangrove subestuaries in Florida Bay, so as to describe temporal variability and infer relationships between Chara cover and water quality that will assist resource managers to restore Chara abundance to historically higher levels. A seasonal pattern of Chara cover was observed in the Alligator Creek subestuary that coincided with seasonal changes in water transparency in a relatively high-nutrient and phytoplankton environment. In contrast, higher Chara cover in the relatively low-nutrient and phytoplankton-abundance McCormick Creek subestuary did not exhibit a repeatable seasonal pattern, but was temporally negatively correlated with salinity and water depth. These observations suggest that water transparency may determine the importance of the salinity driver in these Chara communities. The present study demonstrates the differential importance of water quality and environmental drivers in estuaries distinguished by alternate regimes of phytoplankton and submerged aquatic-vegetation (SAV) dominance, and explains how differences in local estuarine geography may filter the response of SAV communities to environmental stressors.

A materials budget was estimated for the Magela Creek system during the 1982-83 wet season. This tropical system in northern Australia consists largely of a well-defined creek (Magela Creek contributes approximately 50% of the total inflow to the floodplain) flowing into an extensive wetlands area and then into the East Alligator River. Intensive sampling of creek water, rainfall and water flowing from the system provided the data base for the budget calculations. The annual transport of both dissolved and particulate matter by Magela Creek (area 600 km2) is very low, even when compared with other low-relief tropical systems. The annual load transported during 1982-83 was 1260 t (21 kg ha-1) of dissolved salts and 2330 t (39 kg ha-1) of particulate matter. Rainfall appeared to contribute all the sodium, potassium and chloride, and part of the calcium (c. 30%) and magnesium (25%) transported during the 1982-83 wet season by Magela Creek. Most of the manganese (c. 60%) (and probably iron) was contributed from weathering processes occurring in the catchment. Only small amounts of the trace metals copper, lead, zinc and uranium were transported by the creek. During the 1982-83 wet season, more trace metals were contributed in rainfall than transported from the catchment by the creek. However, this is probably atypical and resulted from dust particles that had entered the atmosphere in greater numbers due to the extended dry season. The vast bulk of the nutrients (total P 93%, NO3- N 86%, NH4+ N 98%) added to the catchment by rainfall was removed by the catchment, probably via uptake by the vegetation. Consequently, the creek transported only very small amounts of nutrients to the floodplain. An input-output budget for the Magela floodplain was calculated. The uncertainty in the net amounts deposited or released from the floodplain was estimated using a new quantitative method developed for this purpose. The uncertainties in the net values estimated were high, ranging from around 30% for bicarbonate to 500% for uranium. These data suggest that the Magela floodplain is a net source of the major ions (sodium, potassium, calcium, magnesium, chloride, sulfate and bicarbonate) and also of iron, and a net sink for suspended solids, nutrients (total phosphorus, nitrate and ammonia) and manganese. The floodplain also appears to be a net sink for the trace metals copper, lead, zinc and uranium.

In tropical Australia, intensive studies of river suspended sediment (SS) and nutrient dynamics have been restricted to streams on the north-east coast between the Fitzroy and Normanby Rivers (Queensland), Magela Creek/East Alligator River (Northern Territory) and the Ord River (Western Australia). Historical conditions in these rivers were probably characterised by low–moderate SS concentrations and low concentrations of dissolved inorganic nitrogen and phosphorus in flow events. Introduction of agriculture has transformed SS and nutrient dynamics. Grazing has led to soil erosion and increased SS and particulate nutrient concentrations and fluxes in event flows. Fertilised cropping has increased nutrient inputs to catchments, where it forms a substantial proportion of the catchment area. Consequently, both particulate and dissolved inorganic nutrient concentrations and fluxes have increased. Australian tropical rivers have episodic flows, with most material transport occurring during large flow events. The restricted period of these highly energetic flows means little trapping of materials in waterways occurs. Loads are transported efficiently downstream and processes such as denitrification and in-channel sedimentation may be of limited importance. Owing to excessive nutrient inputs associated with agriculture, a number of northern freshwater, estuarine and coastal ecosystems are now eutrophic. Continued development, especially fertilised cropping, without adequate management of nutrient losses is likely to exacerbate these problems.

The niche axes of microhabitat use, activity and size for 21 skink species from five assemblages (Alligator Creek, Cairns, Chillagoe, Cooktown and Mt Bartle Frere) in the biodiverse tropics of north-east Queensland were examined. Species within the same assemblage separated predominantly along two structural microhabitat gradients; one that ranged from microhabitats dominated by large rocks to leaf litter and total ground cover, and a second defined by increasing leaf litter, ground cover, undergrowth, proximity to vegetation and increased canopy cover. All species used available microhabitats non-randomly, with species from the same ecotype (arboreal, generalist, litter-dwelling, rock-using) clustering in multivariate ecological space. Despite evidence of within-assemblage niche overlap, null-model comparisons revealed that only one assemblage (Chillagoe) had greater niche overlap than would be expected by chance. Assemblages with more species occupied smaller niche space, indicating species packing. However, species with more diverse niches were less evenly packed. While most species overlapped in activity time and body size, differences among species from the same ecotype were observed. Despite subtle differences in temporal activity and body size, differences in structural microhabitat use appears to be the dominant niche axis allowing the coexistence of species within these assemblages of tropical skinks.

Mangroves are a major ecosystem within Kakadu National Park in Australia’s Northern Territory, providing coastal protection, high biodiversity and an important resource for Aboriginal people. In the late Holocene (from c. 6000 before present), mangroves occupied much of the estuarine and coastal plains, but their range has subsequently contracted to the main river systems (the West Alligator, South Alligator and East Alligator Rivers, and the Wildman River), tributary creeks and offshore islands (Field and Barrow Islands). On the basis of maps of mangrove extent generated from aerial photography (1950, 1975, 1984 and 1991), compact airborne spectrographic imagery (CASI; 2002), light detection and ranging (LIDAR; 2011) and RapidEye data (2014 onward), changes in net area have been minor but significant redistribution has occurred, with this being attributed to both inland intrusion and seaward colonisation of mangroves. The greatest area changes have been associated with lower-stature mangroves dominated by Avicennia marina and Sonneratia alba, as determined from these datasets. Aerial surveys, conducted using a remote piloted aircraft (RPA) and fixed wing aircraft in September 2016, showed dieback of mangroves, with spaceborne RapidEye observations suggesting this occurred between late 2015 and 2016 and at the same time as the extensive mangrove losses reported in the Gulf of Carpentaria. Given the recent dieback and the associated need to better monitor and protect mangroves and proximal ecosystems in the World Heritage- and Ramsar-listed Kakadu National Park, the study recommends the development and implementation of a robust and long-term monitoring system that better utilises existing and ongoing earth observation and ground data, and is supported by a national approach.

Context Monitoring populations of long-lived species requires continuous long-term efforts. This is especially applicable for species that have experienced declines range-wide. Aims Our study assessed the current status of a population of wild Macrochelys temminckii and compared the present results to those from a survey conducted nearly a decade ago. Methods Trapping in 2010–2011 was conducted on two creeks within the refuge, during the months of May–July. Capture data were compared with data collected by similar methods in 1997–2001. Key results The population structure of M. temminckii was dominated by juveniles, with few large adults or small juveniles detected and a missing size class was evident. Retrospective analysis of 1997–2001 data revealed that the population was likely to be in decline even then, despite high capture rates. Conclusions The M. temminckii population showed significant declines that indicated that the population had experienced stressors of unknown origin. The status of M. temminckii at the refuge is concerning, given the protection afforded this remnant population. Implications Short-term data from 1997–2001 indicated a healthy M. temminckii population, whereas longer-term data showed that the population has declined, resulting in significant demographic changes. Continued monitoring will be necessary to develop management recommendations and track the impact of implemented management practices. Longer-term monitoring of long-lived vertebrates is required to identify population trends.

The Alligator Pond site is a substantial multi-component prehistoric and historic archaeological site (ca. 1.5 acres) on an upland ridge on the east side of Saline Creek. Saline Creek is a northward-flowing tributary to the Sabine River, and the site is ca. 10 km south of the confluence of Saline Creek with the Sabine River, in the Post Oak Savannah in northern Smith County, Texas. This is the third article that reports on the artifact assemblages from the site. Previous analyses of the artifact assemblages indicate that the principal component is a pre-A.D. 1200 Caddo habitation site, but there is also evidence from temporally diagnostic ceramic sherds and dart points that the site was used to some extent during the Woodland (ca. 500 B.C.-A.D. 800), Late Archaic (ca. 3000-500 B.C.), and Middle Archaic (ca. 6000-3000 B.C.) periods. Finally, there is an early 19th century historic component at the Alligator Pond site that is marked by blade gunflints, glass seed beads, refined earthenware rim and body sherds, possibly pearlware, that have hand-painted floral decorations, and an alkaline-glazed stoneware crock sherd.

A review of early trinomial numbers for sites located in Smith County in East Texas indicated that between 1938 and 1943 Jack Hughes identified and collected from at least 37 sites listed on the Texas Historic Site Atlas. From 1938 to 1941 his site locations randomly occur throughout the County; interestingly there are no sites recorded in 1942. In 1943 he recorded about 14 sites along Black Fork Creek and its tributaries, this being mostly west of the City of Tyler. The primary purpose in reviewing the available archaeological information about these early recorded sites was to re-visit selected sites if necessary and to update information that was recorded beginning almost 80 years ago. An entry contained on a Texas Archeological Research Laboratory at The University of Texas (TARL) site card indicated that Hughes collected artifacts from a site (41SM32) located on Little Saline Creek, near the much better known Alligator Pond site (41SM442) that had been recorded in 2011 by Mark Walters. The Alligator Pond site is on property owned by Thacker, a Texas Archeological Stewardship Network member. 41SM32 is a prehistoric archaeological site that was found and recorded in September 1940 by Jack Hughes, who later went on to a career as a professional archaeologist in Texas. The site is on Little Saline Creek, a northward-flowing tributary to the Sabine River about 10 km to the north, in the Post Oak Savannah of East Texas.

New Year. In this edition of the news I am highlighting several online resources as well as conferences, tours, and exhibits of possible interest.First of all, I highly suggest you sign up at the Alberta School Library Council's new LitPicks site (aslclitpicks.ca). It is free, filled with promise, and includes only books recommended by the reviewers. The reviews are searchable by grade level and genre (e.g., animal, biographical fable, fantasy, humour, historical, horror, verse, realistic, mystery, myth) and include all formats. The reviews include curriculum connections and links to relevant resources. Library staff review titles based on engagement of story, readability, descriptive language, illustration excellence and integrity of data, and source for non-fiction titles. The target users are teachers, teacher-librarians, library techs, and others working in libraries. School library cataloguers can provide a link to the review from within the catalogue record.Another recommended resource is CanLit for Little Canadians, a blog that focuses on promoting children's and YA books by Canadian authors and illustrators. The blog postings can also be found on Facebook. (http://canlitforlittlecanadians.blogspot.ca/)First Nation Communities READ is another resource for your tool box. It is an annual reading program launched in 2003 by the First Nations public library community in Ontario and includes titles that are written and/or illustrated by (or otherwise involve the participation of) a First Nation, Métis, or Inuit creator and contain First Nation, Métis, or Inuit content produced with the support of First Nation, Métis, or Inuit advisers/consultants or First Nation, Métis, or Inuit endorsement. Julie Flett's Wild Berries - Pakwa Che Menisu, available in both English and Cree, was the First Nation Communities Read Selection for 2014-2015 and the inaugural recipient of the Periodical Marketers of Canada Aboriginal Literature Award. (http://www.sols.org/index.php/develop-your-library-staff/advice-consulting/first-nations/fn-communities-read)This resource should also be of great value for those schools and libraries participating in TD Canadian Children’s Book Week in 2015. Each May, authors, illustrators and storytellers visit communities throughout the country to share the delights of Canadian children’s books. Book Week reaches over 25,000 children and teens in schools and libraries across Canada every year. The theme for this year is Hear Our Stories: Celebrating First Nations, Métis and Inuit Literature, celebrating the remarkable variety of topics, genres and voices being published by and about members of our First Nations, Métis and Inuit (FNMI) communities in Canada. On a personal note, I will be touring as a storyteller in Quebec as part of this year’s Book Week tour.Freedom to Read Week: February 22-28, 2015. This annual event encourages Canadians to think about and reaffirm their commitment to intellectual freedom, which is guaranteed them under the Charter of Rights and Freedoms. This year’s Freedom to Read review marks the thirtieth anniversary of its publication and of Freedom to Read Week in Canada. It was first published in 1984 to explore the freedom to read in Canada and elsewhere and to inform and assist booksellers, publishers, librarians, students, educators, writers and the public. To commemorate Freedom to Read’s thirtieth anniversary, some of our writers have cast a look back over the past three decades. As usual, the review provides exercises and resources for teachers, librarians and students. This and previous issues of Freedom to Read, as well as appendices and other resources, are available at www.freedomtoread.ca.Half for you and Half for Me: Nursery Rhymes and Poems we Love. An exhibit on best-loved rhymes and poems and a celebration of the 40th anniversary of Alligator Pie held at the Osborne Collection in the Lillian H. Smith Library in Toronto until March 7, 2015.Serendipity 2015 (March 7, 2015). An exciting day exploring the fabulous world of young adult literature with Holly Black, Andrew Smith, Mariko Tamaki, Molly Idle, and Kelli Chipponeri. Costumes recommended! Swing Space Building, 2175 West Mall on the UBC campus. (http://vclr.ca/serendipity-2015/)For educators: Call for entries for the Martyn Godfrey Young Writers Award (YABS). An annual, juried contest open to all students in Alberta in grades 4 through 9. Students are invited to submit their short stories (500-1500 words) or comic book by March 31, 2015 to the YABS office, 11759 Groat Road, Edmonton, AB, T5M 3K6. Entries may also be emailed to info@yabs.ab.ca.Breaking News: The Canada Council for the Arts has revised the Governor General’s Literary Awards Children’s Literature categories (in consultation with the literary community) in the wake of controversy regarding graphic novels. The revised category titles and definitions:The new Children’s Literature – Illustrated Books category will recognize the best illustrated book for children or young adults, honouring the text and the illustrations as forming one creative work. It includes picture books and graphic novels, as well as works of fiction, literary non-fiction, and poetry where original illustrations occupy at least 30% of the book’s space.The Children’s Literature – Text category will recognize the best book for children or young adults with few (less than 30%) or no illustrations. http://www.bookcentre.ca/news/governor_general%E2%80%99s_literary_awards_revisions_children%E2%80%99s_literature_categoriesGail de Vos, an adjunct instructor, teaches courses on Canadian children's literature, Young Adult Literature and Comic Books and Graphic Novels at the School of Library and Information Studies for the University of Alberta and is the author of nine books on storytelling and folklore. She is a professional storyteller and has taught the storytelling course at SLIS for over two decades.