Journal articles: 'Herring gull behaviour'

1

Goumas, Madeleine, Isabella Burns, Laura A. Kelley, and Neeltje J. Boogert. "Herring gulls respond to human gaze direction." Biology Letters 15, no. 8 (August 2019): 20190405. http://dx.doi.org/10.1098/rsbl.2019.0405.

Full text

Abstract:

Human–wildlife conflict is one of the greatest threats to species populations worldwide. One species facing national declines in the UK is the herring gull ( Larus argentatus ), despite an increase in numbers in urban areas. Gulls in urban areas are often considered a nuisance owing to behaviours such as food-snatching. Whether urban gull feeding behaviour is influenced by human behavioural cues, such as gaze direction, remains unknown. We therefore measured the approach times of herring gulls to a food source placed in close proximity to an experimenter who either looked directly at the gull or looked away. We found that only 26% of targeted gulls would touch the food, suggesting that food-snatching is likely to be conducted by a minority of individuals. When gulls did touch the food, they took significantly longer to approach when the experimenter's gaze was directed towards them compared with directed away. However, inter-individual behaviour varied greatly, with some gulls approaching similarly quickly in both treatments, while others approached much more slowly when the experimenter was looking at them. These results indicate that reducing human–herring gull conflict may be possible through small changes in human behaviour, but will require consideration of behavioural differences between individual gulls.

APA, Harvard, Vancouver, ISO, and other styles

2

Massaro, Melanie, John W. Chardine, Ian L. Jones, and Gregory J. Robertson. "Delayed capelin (Mallotus villosus) availability influences predatory behaviour of large gulls on black-legged kittiwakes (Rissa tridactyla), causing a reduction in kittiwake breeding success." Canadian Journal of Zoology 78, no. 9 (September 1, 2000): 1588–96. http://dx.doi.org/10.1139/z00-085.

Full text

Abstract:

During 1998 and 1999, the impact of predation by herring gulls (Larus argentatus) and great black-backed gulls (Larus marinus) on breeding success of black-legged kittiwakes (Rissa tridactyla) at Gull Island, Witless Bay, southeastern Newfoundland, was quantified in relation to the timing of the annual arrival of capelin (Mallotus villosus) to spawn. The frequency of predation attempts by large gulls on kittiwakes was compared among three periods: before the mean hatching date for herring gulls, between the mean hatching date for herring gulls and the arrival of the capelin, and following capelin arrival. The frequency varied significantly among the three periods, being highest after gull chicks hatched but before the capelin arrived. The frequency of gull predation was significantly correlated with the percentage of kittiwake eggs and chicks that disappeared each week. We estimated that 43 and 30% of kittiwake eggs and chicks at Gull Island were taken by gulls in 1998 and 1999, respectively. Kittiwakes have been indirectly (through increased predation by gulls) affected by the delayed arrival and lower abundance of capelin in recent years, which underlines the need to understand multispecies interactions when interpreting the effects of human alteration of the marine environment.

APA, Harvard, Vancouver, ISO, and other styles

3

Rice, Jake. "Behavioural responses of Common Puffins to kleptoparasitism by Herring Gulls." Canadian Journal of Zoology 65, no. 2 (February 1, 1987): 339–47. http://dx.doi.org/10.1139/z87-053.

Full text

Abstract:

Herring Gulls (Larus argentatus) varied their rates of kleptoparasitic attack depending on Common Puffin (Fratercula arctica) foraging success. Attacks were more frequent on days when many puffins brought back food. However, puffins also varied their behaviour when approaching nest sites with food, so the rate of food loss to gulls per puffin remained constant as the number of puffins with food increased. Site differences in puffin activities after landing reflected only direct consequences of puffin and gull abundances and slope topography. After chick provisioning commenced, puffins at all sites showed increased vigilance after landing and more rapid burrow entries. Behaviour of puffins when approaching the slopes showed adaptations to the presence of gulls. On days when many puffins had food, puffins in areas of high gull density swamped the kleptoparasite. On days when few had food, puffins approached the slopes much as they did before chick provisioning commenced. Hosts as well as kleptoparasites may show closely tuned adaptations to potential food supply and likelihood of attacks.

APA, Harvard, Vancouver, ISO, and other styles

4

Goumas, Madeleine, Neeltje J. Boogert, and Laura A. Kelley. "Urban herring gulls use human behavioural cues to locate food." Royal Society Open Science 7, no. 2 (February 2020): 191959. http://dx.doi.org/10.1098/rsos.191959.

Full text

Abstract:

While many animals are negatively affected by urbanization, some species appear to thrive in urban environments. Herring gulls ( Larus argentatus ) are commonly found in urban areas and often scavenge food discarded by humans. Despite increasing interactions between humans and gulls, little is known about the cognitive underpinnings of urban gull behaviour and to what extent they use human behavioural cues when making foraging decisions. We investigated whether gulls are more attracted to anthropogenic items when they have been handled by a human. We first presented free-living gulls with two identical food objects, one of which was handled, and found that gulls preferentially pecked at the handled food object. We then tested whether gulls' attraction to human-handled objects generalizes to non-food items by presenting a new sample of gulls with two non-food objects, where, again, only one was handled. While similar numbers of gulls approached food and non-food objects in both experiments, they did not peck at handled non-food objects above chance levels. These results suggest that urban gulls generally show low levels of neophobia, but that they use human handling as a cue specifically in the context of food. These behaviours may contribute to gulls’ successful exploitation of urban environments.

APA, Harvard, Vancouver, ISO, and other styles

5

Sutton, Luke J., Ryan A. Burrell, and Seb Loram. "Spatio-temporal trends in the predation of large gulls by peregrine falcons (Falco peregrinus) in an insular breeding population." Slovak Raptor Journal 11, no. 1 (December 1, 2017): 103–9. http://dx.doi.org/10.1515/srj-2017-0002.

Full text

Abstract:

Abstract Individual diet specialization occurs in many populations of generalist predators, with specific individuals developing specialist strategies in their feeding behaviour. Intraspecific resource partitioning is hypothesised to be common amongst species in higher trophic levels where competition for resources is intense, and a key driver in breeding success and community structure. Though well-studied in other predators, there is sparse data on ecological specialization in raptors, which are important drivers of community and trophic structure. In this study, the breeding season diet of an insular population of peregrine falcons (Falco peregrinus) was determined from indirect analysis of prey remains collected over three years. An unexpected result was the high proportion of large gulls (Laridae), of the genus Larus, in the diet of two breeding pairs of peregrines. Large gulls made up 18.44% by frequency of total prey recorded and 30.81% by biomass. Herring gulls (Larus argentatus) were the most common large gull prey, with immatures most frequent (67.95%) compared to adults (19.23%). Overall, most gulls predated were immatures (80.77%). Frequency of predation varied between breeding pairs and months, but was consistent over the three years. Most gulls were taken in April (37.17%), followed by May (19.23%), with a smaller peak of immature herring gulls taken in August and September. The pattern of regular predation by peregrines on large gulls is a new observation with important implications for understanding individual diet specialization in raptors, and its effect on bird populations and community structure.

APA, Harvard, Vancouver, ISO, and other styles

6

Hébert, Percy N., and Robert M. R. Barclay. "Asynchronous and synchronous hatching: effect on early growth and survivorship of Herring Gull, Larus argentatus, chicks." Canadian Journal of Zoology 64, no. 10 (October 1, 1986): 2357–62. http://dx.doi.org/10.1139/z86-351.

Full text

Abstract:

The adaptive significance of asynchronous hatching in the Herring Gull, Larus argentatus, was examined during the summer of 1984 at Kent Island, New Brunswick. Chick growth and behaviour in 28 experimental three-egg clutches in which the eggs hatched synchronously (i.e., hatch interval ≤ 24 h between the first (A chick) and last (C chick) hatched) were compared with that of 15 control three-egg nests with normal hatching asynchrony (A–C hatch interval > 24 h). All chicks had similar hatch weights, except for control C chicks, which on average were significantly lighter than their nest mates and experimental chicks. Growth rates were also similar for all chicks within and between groups, except for control C chicks, which grew at a significantly slower rate compared with nest mates and experimental chicks. In control broods, C chicks disappeared first significantly more often than A or B chicks. In experimental broods, a similar proportion of A, B, and C chicks disappeared first. Survivorship, through to day 5 posthatch, was significantly lower for control C chicks than for control A and B chicks as well as experimental chicks. These results suggest that the benefit Herring Gulls achieve hatching their eggs asynchronously results from the competitive advantage accrued to the A chick (and the B chick to some degree), which allows them to obtain more food, especially during periods of food stress. Subsequently the probability of survival of the older, more fit chick(s) is enhanced.

APA, Harvard, Vancouver, ISO, and other styles

7

Robertson, Gregory J., David Fifield, Melanie Massaro, and John W. Chardine. "Changes in nesting-habitat use of large gulls breeding in Witless Bay, Newfoundland." Canadian Journal of Zoology 79, no. 12 (December 1, 2001): 2159–67. http://dx.doi.org/10.1139/z01-180.

Full text

Abstract:

We counted herring gull (Larus argentatus) and great black-backed gull (Larus marinus) nests in the Witless Bay Seabird Ecological Reserve in southeastern Newfoundland, Canada, in 1999 and 2000 and compared our results with previous nest counts from the 1970s. On Gull Island, herring gull nest numbers were 27.5% (1999) and 30.0% (2000) lower than in 1979. Similarly, on Great Island, by 2000 the numbers of herring gull nests had declined 40.8% from numbers in 1979. Counts of great black-backed gull nests were more variable, but suggest a slight or no reduction since 1979. Numbers of herring gulls nesting in rocky and puffin-slope habitats were much reduced (5070%), while numbers nesting in meadows and forests have actually increased since the 1970s. Great black-backed gulls showed a similar change in nesting distribution. For herring gulls, these changes in nesting numbers matched differences in reproductive success previously documented in these habitats. We suggest that the decline in gull numbers and the change in breeding-habitat selection were caused by changes in the food availability for gulls. Reduced amounts of fisheries offal and the delayed arrival onshore of capelin (Mallotus villosus), an important fish prey species for gulls, have all likely led to the decline in gull reproductive output. Gulls nesting in meadows and forests may be maintaining adequate reproductive output by focusing on alternative prey, such as adult Leach's storm-petrels (Oceanodroma leucorhoa), rather than scarce refuse and fish.

APA, Harvard, Vancouver, ISO, and other styles

8

Hollmén, Tuula, J. Christian Franson, Douglas E. Docherty, Mikael Kilpi, Martti Hario, Lynn H. Creekmore, and Margaret R. Petersen. "Infectious Bursal Disease Virus Antibodies in Eider Ducks and Herring Gulls." Condor 102, no. 3 (August 1, 2000): 688–91. http://dx.doi.org/10.1093/condor/102.3.688.

Full text

Abstract:

Abstract We measured antibodies to infectious bursal disease virus (IBDV) in blood of nesting Common Eider (Somateria mollissima) females and immature Herring Gulls (Larus argentatus) in the Baltic Sea, and in blood of Spectacled Eider (Somateria fischeri) females nesting in a remote area of western Alaska. Positive (≥ 1:16) IBDV titers occurred in 75% of the eiders and 45% of the Herring Gull chicks. In eiders, the prevalence of positive titers differed among locations. We found no evidence that IBDV exposure impaired the immune function of Herring Gull chicks, based on their response to inoculation of sheep red blood cells. We suggest that eider ducks and Herring Gulls have been exposed to IBDV, even in locations where contact with poultry is unlikely. The presence of this virus in wild bird populations is of concern because it causes mortality of up to 30% in susceptible poultry.

APA, Harvard, Vancouver, ISO, and other styles

9

Garthe, Stefan, and Birgit Scherp. "Utilization of discards and offal from commercial fisheries by seabirds in the Baltic Sea." ICES Journal of Marine Science 60, no. 5 (January 1, 2003): 980–89. http://dx.doi.org/10.1016/s1054-3139(03)00099-7.

Full text

Abstract:

Abstract The distribution and abundance of scavenging seabirds and their utilization of discards and offal between June and December 1998 were studied in the western Baltic Sea. Herring gulls were clearly the most numerous scavenging species in all areas and all seasons, followed by great black-backed gulls, lesser black-backed gulls and mew gulls. High percentages of discarded gadoids (cod, whiting), clupeids (herring, sprat), scad, rockling and offal were consumed by seabirds during experimental discarding on fishing boats, whereas the percentages of flatfish consumed were extremely low. There was a clear effect of cod length on total and species-specific consumption by birds but this pattern was hardly evident for clupeids or dab. By combining official discard and offal statistics and our experimental discarding, we estimate that 6500 t of fish discards and 16 000 t of offal were consumed annually by seabirds in the Baltic Sea. Bivalves, especially blue mussels Mytilus edulis, were the most frequently represented food item in herring gull pellets. Fish identified in the pellets consisted mainly of gadoids, in particular cod. The proportion of discards in herring gull pellets was on average 1.6% (range: 0–4.5%) at Laboe and 17.5% at Warnemünde (range: 9.4–25.5%), but pellets bias diet assessment as offal and other soft prey (including clupeids) will be under-represented. Scavenging on discards and offal is a widespread phenomenon in the Baltic Sea as it is in other shelf areas of Europe, but the number of bird species involved is generally lower and strongly biased towards gulls, especially herring gulls.

APA, Harvard, Vancouver, ISO, and other styles

10

Rice, Jake. "Interactions of variation in food supply and kleptoparasitism levels on the reproductive success of Common Puffins (Fratercula arctica)." Canadian Journal of Zoology 63, no. 12 (December 1, 1985): 2743–47. http://dx.doi.org/10.1139/z85-409.

Full text

Abstract:

Colonies of Common Puffins (Fratercula arctica), differing in numbers of breeding Herring Gulls (Larus argentatus) present, also differed in puffin numbers, burrow placement, and burrow activity rate. All differences indicated that puffins avoided gulls. Sites differing in gull numbers did not differ, however, in puffin fledging success or weights of fledged chicks. Chick weights and fledging success were low. The pattern of weight gain by chicks was irregular over the season, although consistent among sites for individual periods. These results imply that food usually was hard to find, although occasionally locally abundant. Pressures on puffin reproductive efforts due to variation in food supply and levels of kleptoparasitism do not appear to be additive; rather, low food availability decreases the effect of gull kleptoparasitism as well.

APA, Harvard, Vancouver, ISO, and other styles

11

Hebert, Craig E., J. Laird Shutt, Keith A. Hobson, and DV Chip Weseloh. "Spatial and temporal differences in the diet of Great Lakes herring gulls (Larus argentatus): evidence from stable isotope analysis." Canadian Journal of Fisheries and Aquatic Sciences 56, no. 2 (February 1, 1999): 323–38. http://dx.doi.org/10.1139/f98-189.

Full text

Abstract:

Stable nitrogen (δ15N) and carbon (δ13C) isotope values were measured in lipid-free homogenates of herring gull (Larus argentatus) eggs collected from the Laurentian Great Lakes during 1974-1995. δ15N values provided an indication of adult gull trophic position during egg formation. After adjustment of egg δ15N values for interlake differences in baseline food web δ15N signatures, significant differences in gull trophic position were found among colonies. These results were attributed to differing proportions of fish in the diets of gulls from the various colonies. Aquatic foods available to gulls had greater δ15N values than terrestrial foods. δ13C measurements provided some support for our hypothesis that terrestrial foods, particularly garbage, were more enriched in 13C than aquatic foods. As the proportion of fish in the diet decreased, the fraction consisting of terrestrial food increased, resulting in an increase in δ13C values and a decline in δ15N values. Stable isotope values for gull eggs from Lake Erie changed significantly during the study period and may have reflected a decline in fish availability.

APA, Harvard, Vancouver, ISO, and other styles

12

Whittam, Rebecca M., and Marty L. Leonard. "Characteristics of Predators and Offspring Influence Nest Defense by Arctic and Common Terns." Condor 102, no. 2 (May 1, 2000): 301–6. http://dx.doi.org/10.1093/condor/102.2.301.

Full text

Abstract:

Abstract Nest defense is a critical aspect of parental care that entails both costs and benefits. The purpose of this study was to examine patterns of nest defense in a colony of Arctic and Common Terns (Sterna paradisaea and S. hirundo, respectively) using observations of natural predators: Herring Gulls (Larus argentatus) and Great Black-backed Gulls (L. marinus). Tern nest-defense scores were higher for hunting gulls than for overflying gulls and for gull flights closer to the ground. Defense scores also were significantly higher during the chick stage than during the egg stage. Within the chick stage, response score initially increased with age, but then declined. The results of this study indicate that terns vary their defense in relation to characteristics of predators and offspring that influence the costs and benefits of defense.

APA, Harvard, Vancouver, ISO, and other styles

13

Fox, G. A., L. J. Allan, D. V. Weseloh, and P. Mineau. "The diet of herring gulls during the nesting period in Canadian waters of the Great Lakes." Canadian Journal of Zoology 68, no. 6 (June 1, 1990): 1075–85. http://dx.doi.org/10.1139/z90-159.

Full text

Abstract:

We report the content of 132 boli and 2000 pellets regurgitated by adults and 1749 boli regurgitated for or by chicks in 25 herring gull (Larus argentatus) colonies in Lakes Ontario, Erie, Huron and Superior, between mid-April and mid-July, 1977–1983. Fish were the predominant food in all four lakes. Although 11 families of fish and a minimum of 16 species were identified, 80% of the fish were of two exotic species, the alewife (Alosa pseudoharengus) and the rainbow smelt (Osmerus mordax). The dietary importance of these two fish species reflected their relative abundance within a lake. In addition, representatives of eight orders of insects and 11 families of birds were identified. In the one colony where diets of birds of known sex were quantified, male and female gulls fed on different proportions of alewife and smelt, suggesting the sexes have different foraging strategies. Although some food was scavenged, most was obtained alive. Dietary differences existed between colonies and between lakes, both within and between years. We suggest that diet, contaminant burden, and population size of Great Lakes herring gulls will be affected by fisheries policies which alter the predator–prey dynamics of this exotic-dominated ecosystem.

APA, Harvard, Vancouver, ISO, and other styles

14

Rönkkönen, Sanna, Evald Ojaveer, Tiit Raid, and Markku Viitasalo. "Long-term changes in Baltic herring (Clupea harengus membras) growth in the Gulf of Finland." Canadian Journal of Fisheries and Aquatic Sciences 61, no. 2 (February 1, 2004): 219–29. http://dx.doi.org/10.1139/f03-167.

Full text

Abstract:

We used the longest available weight-at-age (WAA) time series (from 1950 to 1999) for Baltic herring (Clupea harengus membras L.) in the Gulf of Finland to investigate which environmental factors affect Baltic herring growth. The relationships among WAAs, annual weight increments, and growth rates for different herring year classes, water salinity, temperature, zooplankton abundance, and biomass, as well as stock sizes of herring, sprat, and cod, were evaluated. Our results showed that in the Gulf of Finland, herring weight and growth rate correlated positively with salinity, and WAA correlated positively with the abundance of the marine zooplankton species Pseudocalanus minutus elongatus. A density-dependent mechanism was not likely to explain the changes in herring WAA in the Gulf of Finland, because no significant correlation between herring WAAs and herring abundance could be found. Instead, the zooplankton community structure changed during the research period, which supports the theory of bottom-up controlling mechanism. A strong negative correlation between herring weight and sprat biomass may indicate competition for food between these species.

APA, Harvard, Vancouver, ISO, and other styles

15

Chadwick, E. M. P., D. K. Cairns, H. M. C. Dupuis, K. V. Ewart, M. H. Kao, and G. L. Fletcher. "Plasma Antifreeze Levels Reflect the Migratory Behaviour of Atlantic Herring (Clupea harengus harengus) in the Southern Gulf of St. Lawrence." Canadian Journal of Fisheries and Aquatic Sciences 47, no. 8 (August 1, 1990): 1534–36. http://dx.doi.org/10.1139/f90-172.

Full text

Abstract:

This study compared freeze protection conferred by blood antifreeze proteins to juvenile and adult Atlantic herring (Clupea harengus harengus) in the southern Gulf of St. Lawrence in December 1988. Juvenile herring had significantly lower plasma freezing points and significantly higher antifreeze activity than adults. Differences in antifreeze activity and in late autumn distribution suggest that juvenile herring are more capable of wintering in the Gulf of St. Lawrence than adults. This conclusion is consistent with our observation that during December, juveniles were present in shallow waters of Chaleur Bay, which is ice-covered during winter, while adults were found only in the deeper waters of Sydney Bight, which do not freeze during winter.

APA, Harvard, Vancouver, ISO, and other styles

16

Martin, Kathy. "Herring gulls prey upon female willow ptarmigan." Canadian Journal of Zoology 63, no. 4 (April 1, 1985): 984–85. http://dx.doi.org/10.1139/z85-146.

Full text

Abstract:

On 12 June 1984 at La Pérouse Bay, Manitoba, Canada, 1 saw three herring gulls attack, kill, and consume an incubating adult hen willow ptarmigan and her clutch despite vigorous defence behaviour by her mate. Possible attacks by gulls or jaegers occurred also on two incubating hens in 1983.

APA, Harvard, Vancouver, ISO, and other styles

17

Scopel, L. C., and A. W. Diamond. "Predation and food–weather interactions drive colony collapse in a managed metapopulation of Arctic Terns (Sterna paradisaea)." Canadian Journal of Zoology 96, no. 1 (January 2018): 13–22. http://dx.doi.org/10.1139/cjz-2016-0281.

Full text

Abstract:

Seabirds are considered bioindicators of bottom-up ecosystem processes, owing to seabirds’ dependence on marine prey. However, ground-nesting seabirds are susceptible to predation, which can limit their use as bioindicators. Machias Seal Island (MSI) supported the largest colony of Arctic Terns (Sterna paradisaea Pontoppidan, 1763) in the Gulf of Maine metapopulation, but prolonged breeding failure led ∼90% of terns to abandon the colony in 2006. We analyzed 12 years of food, weather, and predation data using logistic regression models to determine which had the strongest influence on breeding success. Food–weather interactions were important; under low rainfall, more euphausiids (northern krill, Meganyctiphanes norvegica (M. Sars, 1857)) in the diet increased breeding success, but euphausiids had a negative effect as rainfall became moderate or high. Predation by Herring Gulls (Larus argentatus Pontoppidan, 1763) increased following the cessation of lethal predator control; we identified a predation threshold of 25%, beyond which terns could not breed successfully. The collapse of MSI’s tern colony can be attributed entirely to gull predation. The breeding success of terns at MSI cannot be used as a bottom-up ecosystem bioindicator without accounting for predation. Managers of ground-nesting seabirds should consider predation and food as equally valid potential causes of population or reproductive declines.

APA, Harvard, Vancouver, ISO, and other styles

18

Sobey, Douglas G. "THE DEFAECATING BEHAVIOUR OF HERRING GULLS LARUS ARGENTATUS." Ibis 119, no. 4 (April 3, 2008): 515–20. http://dx.doi.org/10.1111/j.1474-919x.1977.tb02059.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

19

Jones, Orrin E., Paul M. Castelli, and Christopher K. Williams. "Observed Herring Gull Kleptoparasitism of American Black Ducks." Journal of Fish and Wildlife Management 2, no. 2 (December 1, 2011): 196–98. http://dx.doi.org/10.3996/062011-jfwm-035.

Full text

Abstract:

Abstract Herring gulls Larus argentatus were observed to kleptoparasitize American black ducks Anas rubripes feeding on fiddler crabs Uca pugnax in coastal New Jersey. Although widespread in Laridae, kleptoparasitism has never been described between these two species. Over two winters of intensive 24-hour behavioral observations, this interaction was observed on two occasions during similar tidal conditions. Although this appears to be a rare interaction with limited energetic consequences, we note that quantifying these uncommon interspecific interactions is a benefit of thorough behavior observations, which may refine estimates of daily energy expenditure.

APA, Harvard, Vancouver, ISO, and other styles

20

Massaro, Melanie, John W. Chardine, and Ian L. Jones. "Relationships Between Black-Legged Kittiwake Nest-Site Characteristics and Susceptibility to Predation by Large Gulls." Condor 103, no. 4 (November 1, 2001): 793–801. http://dx.doi.org/10.1093/condor/103.4.793.

Full text

Abstract:

Abstract We quantified the relationship between Black-legged Kittiwake (Rissa tridactyla) nest-site characteristics and risk of predation by Great Black-backed (Larus marinus) and Herring (L. argentatus) Gulls at Gull Island, Newfoundland, Canada, during 1998 and 1999. We monitored kittiwake nesting cliffs to identify nest sites attacked by large gulls and compared characteristics of attacked and successful nests among four study plots. We also examined which nest sites were attacked by Herring or Great Black-backed Gulls during calm (≤10 km hr−1) or windy conditions (>10 km hr−1). We found that kittiwake nests on plots with fewer nests were more likely to be attacked by gulls and less likely to fledge young. Nest density and nest location relative to the cliffs' upper edges significantly affected the risk of gull predation. Breeding success was correlated with nest density and ledge width and differed significantly among plots. Regardless of wind conditions both gull species were more likely to attack nests located on upper sections of cliffs than nests on lower sections. However, during calm conditions, nest sites located on narrow ledges were less likely to be attacked by Great Black-backed Gulls. Our results demonstrate that for kittiwake colonies where predation is an important source of breeding failure, the size of subcolonies and nest density affect the survival of kittiwake offspring. Relación entre las Características de los Sitios de Nidificación de Rissa tridactyla y la Susceptibilidad a la Depredación por parte de Gaviotas Resumen. Cuantificamos la relación entre las características de los sitios de nidificación de Rissa tridactyla y el riesgo de depredación por parte de Larus marinus y L. argentatus en la Isla Gull, Newfoundland, Canadá, durante 1998 y 1999. Con el objetivo de identificar los nidos atacados por gaviotas de gran tamaño, monitoreamos acantilados de nidificación de R. tridactyla en cuatro localidades de estudio y comparamos las características de los nidos atacados y exitosos. También examinamos qué nidos fueron atacados por L. marinus o por L. argentatus durante condiciones de viento calmo (≤10 km hr−1) o ventosas (>10 km hr−1). Encontramos que los nidos de R. tridactyla ubicados en localidades con menor número de nidos tuvieron mayor probabilidad de ser atacados y menor probabilidad de criar volantones. Tanto la densidad como la ubicación de los nidos en relación al vértice superior del acantilado afectaron significativamente el riesgo de depredación por gaviotas. El éxito de cría se diferenció significativamente entre localidades y se correlacionó con la densidad de nidos y con el ancho de la plataforma. Independientemente de la velocidad del viento, las dos especies de gaviotas atacaron con mayor probabilidad a los nidos ubicados en las secciones superiores del acantilado que en las secciones inferiores. Sin embargo, durante condiciones de viento calmo, los nidos localizados en plataformas angostas presentaron una menor probabilidad de ser atacados por L. marinus. Nuestros resultados demuestran que para colonias de R. tridactyla en las cuales la depredación de nidos es un factor importante en el fracaso reproductivo, el tamaño de las subcolonias y la densidad de nidos afecta la supervivencia de la progenie de R. tridactyla.

APA, Harvard, Vancouver, ISO, and other styles

21

Morris, Ralph D., and John W. Chardine. "The effects of ice cover over the colony site on reproductive activities of herring gulls." Canadian Journal of Zoology 63, no. 3 (March 1, 1985): 607–11. http://dx.doi.org/10.1139/z85-088.

Full text

Abstract:

The substrate at a herring gull (Larus argentatus) colony on Lake Erie near Port Colborne, Ontario (Lighthouse), was completely covered by a thick layer of ice throughout April and early May 1982. Egg laying normally begins at this location in mid-April. An adjacent herring gull colony (Canada Furnace) was ice free. Herring gull pairs at the Lighthouse colony defended territories on top of the ice but only 3 of about 90 pairs built nests on the ice. Birds neither deserted the colony nor moved within it to ice-free areas as these became available. The mean date of egg laying at the Lighthouse colony in 1982 was about 2 weeks later than in the previous year. At the adjacent Canada Furnace colony, there was no difference in the mean date of egg laying between the 2 years. There were no differences in the distribution of clutch sizes, mean clutch sizes, or hatching success of three-egg clutches laid within ± 1 SD of the mean date of egg laying at either colony in the 2 years. By these measures, the ice-induced delay in breeding chronology of birds at the Lighthouse colony in 1982 did not adversely effect reproductive performance in that year.

APA, Harvard, Vancouver, ISO, and other styles

22

Coulson, J. C., P. Monaghan, and S. A. Greig. "Feeding Strategies of Male and Female Adult Herring Gulls (Larus Argentatus)." Behaviour 94, no. 1-2 (1985): 41–59. http://dx.doi.org/10.1163/156853985x00262.

Full text

Abstract:

AbstractThis paper examines the foraging behaviour of adult male and female herring gulls at refuse tips during winter. Although the majority of herring gulls were either on the tip or nearby for much of the daylight period, an individual male or female fed at the tip for only 30 minutes per day. Three types of feeding were distinguished: (a) undisturbed primary feeding on freshly dumped refuse; (b) disturbed primary feeding where the gulls fed whilst a bulldozer was moving the refuse; and (c) secondary feeding on dispersed refuse partially covered with earth. During primary feeding the herring gulls fed at high density and the feeding flock comprised 73% adults whilst during secondary feeding they were at low density and the flock contained only 25 % adults. A comparison of disturbed and undisturbed primary feeding showed that the birds dipped for food from the air in the former but searched for food on the ground in the latter. This resulted in eight times more encounters per individual and much greater competition in undisturbed feeding. Proportionally more adult male than female herring gulls participated in undisturbed (i.e. competitive) feeding, whereas the reverse was true of disturbed feeding. These differences were greatest in the first half of the winter (i.e. October-mid-December). There were no differences in the sex-ratio of those participating in secondary feeding. During undisturbed primary feeding adult females had higher pecking and walking rates and lower encounter rates than males. Males obtained at least a fifth of their food by attacking and displacing other feeding herring gulls, three times more than females. Female herring gulls fed more often on the edge of the refuse pile where competitive interactions were less frequent but also where foraging success was lower. As the undisturbed feeding bout progressed, attack rates of males increased and their swallowing rate was sustained. In contrast, the attack rates of females decreased as did the swallowing rates. The proportion of females present also decreased, suggesting that some females were responding to the increased levels of aggression by leaving the feeding area. Refuse tips provide a variety of feeding opportunities. In a competitive feeding situation the smaller female herring gulls are disadvantaged by the dominance of males. In disturbed feeding they are able to compensate to some extent because their smaller size results in greater manoeuvrability.

APA, Harvard, Vancouver, ISO, and other styles

23

McGladdery, S. E., and M. D. B. Burt. "Potential of Parasites for Use as Biological Indicators of Migration, Feeding, and Spawning Behavior of Northwestern Atlantic Herring (Clupea harengus)." Canadian Journal of Fisheries and Aquatic Sciences 42, no. 12 (December 1, 1985): 1957–68. http://dx.doi.org/10.1139/f85-243.

Full text

Abstract:

A parasite survey of Atlantic herring, Clupea harengus, collected from the Bay of Fundy, Nova Scotian Shelf, and Gulf of St. Lawrence, was conducted from May 1981 to November 1983. A total of 2380 herring were examined and 18 parasite species identified. These included the acanthocephalan Echinorhynchus gadi previously unreported from herring in the northwestern Atlantic and the monogenean Gyrodactyloides andriaschewski herein described from herring for the first time. The geographic distributions of the parasites, their seasonal dynamics, and relation to size of herring were recorded to determine whether they could be used as biological indicators, both to differentiate between individual herring populations and to determine their movements. Seven of the 18 species identified showed varying degrees of potential as biological indicators. Although no single parasite species was found which could clearly differentiate one population of herring from another, the differential prevalences and intensities of Anisakis simplex, Hysterothylacium aduncum, Derogenes varicus, Lecithaster gibbosus, Cryptocotyle lingua, Scolex pleuronectis, and Eimeria sardinae all provided valuable contributions to the knowledge already accumulated on herring migration, feeding, and spawning behavior. Parasite indicators, used in conjunction with other data and techniques, could eventually be used to distinguish between individual populations of herring.

APA, Harvard, Vancouver, ISO, and other styles

24

Coulson, J. C., and J. Butterfield. "Movements of British Herring Gulls." Bird Study 32, no. 2 (July 1985): 91–103. http://dx.doi.org/10.1080/00063658509476863.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Rahikainen, Mika, Kirsi-Maaria Hoviniemi, Samu Mäntyniemi, Jarno Vanhatalo, Inari Helle, Maiju Lehtiniemi, Jukka Pönni, and Sakari Kuikka. "Impacts of eutrophication and oil spills on the Gulf of Finland herring stock." Canadian Journal of Fisheries and Aquatic Sciences 74, no. 8 (August 2017): 1218–32. http://dx.doi.org/10.1139/cjfas-2016-0108.

Full text

Abstract:

The Baltic Sea is one of the world’s most stressed sea areas. Major threats to the ecosystem include eutrophication and oil spills. The progression of anthropogenic nutrient enrichment is lengthy and gradual, while oil spills cause rapid changes in the system, with varying impact time. We quantify the impact of eutrophication and the key ecological covariates on the population dynamics of the major pelagic fish stock, the Baltic herring (Clupea harengus membras), in the Gulf of Finland. The full life cycle of herring is represented with a probabilistic state-space model. Moreover, we analyse the impact of the oil spill from M/T Antonio Gramsci in 1987 on herring survival. The results confirm impact of the spill on the early life-stage survival; the observed high frequency of malformed herring larvae in surveys signaled elevated mortality of the year class. The optimal July–August chlorophyll a concentration for herring reproduction is approximately 5 μg·L−1. This level is currently exceeded, suggesting recruitment impairment due to eutrophication. The herring stock was also recruitment-overfished. Analysis suggests deceleration of herring growth as salinity descends below 6 psu.

APA, Harvard, Vancouver, ISO, and other styles

26

Gobeil, Robert E. "Arterial system of the Herring gull (Larus argentatus)." Journal of Zoology 160, no. 3 (August 20, 2009): 337–54. http://dx.doi.org/10.1111/j.1469-7998.1970.tb03085.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Farmer, R. G., and M. L. Leonard. "Long-term feeding ecology of Great Black-backed Gulls (Larus marinus) in the northwest Atlantic: 110 years of feather isotope data." Canadian Journal of Zoology 89, no. 2 (February 2011): 123–33. http://dx.doi.org/10.1139/z10-102.

Full text

Abstract:

Recent changes to the ecology of the northwest Atlantic are affecting feeding relationships at many trophic levels. With declining fish stocks and fewer fisheries discards, generalist birds such as Great Black-backed Gulls ( Larus marinus L., 1758) may shift their diets. To test whether such a change has occurred, we measured stable nitrogen and carbon isotope ratios of flight feathers collected from modern and museum-preserved birds (1896–2006). We then compared trends in isotope ratios with trends in regional fisheries productivity to determine if gull diets and fisheries changes were associated. We found a significant decline in stable nitrogen isotope ratios of feathers over time, indicating that the gulls’ trophic feeding level has decreased by approximately 2.26‰, or 0.82 trophic units. In contrast, we found no significant change in carbon isotope ratios, giving no clear evidence for a shift to more offshore or terrestrial foraging. The declining stable nitrogen ratio was significantly and positively correlated with both regional groundfish captures and regional fisheries trophic level, and was negatively correlated with each of (i) crab captures and (ii) herring, sardine, and anchovy captures. Our study gives evidence for a shift in diets of Great Black-backed Gulls over time and further suggests that these changes may be related to ongoing changes in fisheries.

APA, Harvard, Vancouver, ISO, and other styles

28

Gamble, Jennifer R., and Daniel A. Cristol. "Drop-catch behaviour is play in herring gulls, Larus argentatus." Animal Behaviour 63, no. 2 (February 2002): 339–45. http://dx.doi.org/10.1006/anbe.2001.1903.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Spear, Philip A., Thomas W. Moon, and David B. Peakall. "Liver retinoid concentrations in natural populations of herring gulls (Larus argentatus) contaminated by 2,3,7,8-tetrachlorodibenzo-p-dioxin and in ring doves (Streptopelia risoria) injected with a dioxin analogue." Canadian Journal of Zoology 64, no. 1 (January 1, 1986): 204–8. http://dx.doi.org/10.1139/z86-032.

Full text

Abstract:

Liver vitamin A was analysed by reverse phase high pressure liquid chromatography in a limited number of herring gull samples collected from New Brunswick coastal and Great Lakes colonies. Both retinol and retinyl palmitate concentrations were significantly different between the New Brunswick and Great Lakes colonies as well as among the Great Lakes colonies. The highest mean values were 864 and 1737 μg/g retinol and retinyl palmitate, respectively, occurring in the New Brunswick gulls. The lowest mean values were 131 and 231 μg/g retinol and retinyl palmitate, respectively, which were detected in Lake Ontario gulls. Retinoid levels were inversely related to the extent of dioxin contamination reported previously. Ring doves received single low-level doses of the dioxin analogue 3,4,3′,4′-tetrachlorobiphenyl and were sacrificed at various times postinjection. Liver retinol decreased significantly as aryl hydrocarbon hydroxylase activity increased. The decrease in retinol concentration was not related to UDP-glucuronyltransferase activity. Retinyl palmitate was unaffected by the analogue under the conditions of this study. These results support the hypothesis that, in wildlife species, hepatic retinoid metabolism is affected by chlorinated dibenzodioxins or other contaminants capable of inducing aryl hydrocarbon hydroxylase.

APA, Harvard, Vancouver, ISO, and other styles

30

Threlfall, William, and Nicole A. Roy. "Skull Deformity in a Herring Gull Chick (Larus argentatus)." Journal of Wildlife Diseases 24, no. 1 (January 1988): 133–36. http://dx.doi.org/10.7589/0090-3558-24.1.133.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

Anthony, V. C., and M. J. Fogarty. "Environmental Effects on Recruitment, Growth, and Vulnerability of Atlantic Herring (Clupea harengus harengus) in the Gulf of Maine Region." Canadian Journal of Fisheries and Aquatic Sciences 42, S1 (December 19, 1985): s158—s173. http://dx.doi.org/10.1139/f85-271.

Full text

Abstract:

Atlantic herring (Clupea harengus harengus) recruitment in the Gulf of Maine since 1947 has varied by a ratio of 20 to 1. Since heavy fishing began in the mid-1960's, recruitment has fluctuated by only a factor of 9 to 1. The greatest fluctuations in recruitment, therefore, historically occurred in the absence of high fishing mortality. Recruitment predictions and understanding of the causes of fluctuations are extremely important, since strong year classes traditionally have sustained the herring fisheries in the Gulf of Maine. The effect of environmental variables (particularly temperature) on herring recruitment and growth were examined in detail. Vulnerability of Gulf of Maine herring in response to moon phase is also considered. Indices of abundance of Atlantic herring in the Gulf of Maine were calculated for three time periods using three different procedures. Indices of abundance for the periods of 1915–67 and 1951–81 indicated that productivity, or amount of recruitment per amount of spawning stock, was positively related to temperature or other factors (e.g. food availability) related to temperature at intermediate to high levels of spawning stock biomass. For the shorter and most recent time period (1965–81), abundance was calculated by virtual population analysis and an attempt was made to relate temperature effects during several periods in the first year of life to recruitment levels at age 2. The mean, maximum, and minimum water temperatures during (1) September–December (spawning – early larval development), (2) January–April (overwintering and late larval development), and (3) May–August (postlarval) periods were correlated with abundance. Significant effects of mean and minimum temperature during period 2 and minimum temperature during period 3 were observed, suggesting that environmental influences on determination of year class strength occur during late larval – early juvenile phases. Possible reasons for the discrepancy between the long-term analyses bases on abundance indices and the more detailed analyses using population size estimates based on virtual population analysis are discussed. An indication of environmental limitation is also shown by density-dependent growth. Growth appears to be related to both age 2 abundance and summer water temperature. When abundance is great, its effect overcomes the positive effect of temperature (or other factors indicated by temperature). The environment also alters the availability and vulnerability of herring to the inshore fisheries. Young herring are more available and vulnerable to fixed gear during the dark phase of the moon. This effect is pronounced when abundance is low.

APA, Harvard, Vancouver, ISO, and other styles

32

Young, Andrew D., and Rodger D. Titman. "Costs and benefits to Red-breasted Mergansers nesting in tern and gull colonies." Canadian Journal of Zoology 64, no. 10 (October 1, 1986): 2339–43. http://dx.doi.org/10.1139/z86-348.

Full text

Abstract:

The costs and benefits to Red-breasted Mergansers (Mergus serrator) nesting in a Common Tern (Sterna hirundo) colony and a Herring Gull (Larus argentatus) and Great Black-backed Gull (L. marinus) colony were studied from 5 June to 17 August 1984 on islands off the east coast of New Brunswick. Merganser nests outside larid colonies were preyed upon significantly more than nests in the tern colony while no difference was found with nests in the gull colony. Nests in the tern colony were more densely concentrated and more likely to be abandoned. Clumped nests in the tern colony were not initiated in greater synchrony than dispersed nests. The merganser–gull nesting association is discussed. We postulate that the protective benefit for merganser nests in tern colonies accounts for the evolution of the nesting association.

APA, Harvard, Vancouver, ISO, and other styles

33

Tinbergen., N. "OK THE SIGNIFICANCE OF TERRITORY IN THE HERRING GULL." Ibis 94, no. 1 (April 3, 2008): 158–59. http://dx.doi.org/10.1111/j.1474-919x.1952.tb01796.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Stienen, Eric W. M., and Alex Brenninkmeijer. "Foraging Decisions of Sandwich Terns in the Presence of Kleptoparasitising Gulls." Auk 119, no. 2 (April 1, 2002): 473–86. http://dx.doi.org/10.1093/auk/119.2.473.

Full text

Abstract:

AbstractWe studied prey selection of Sandwich Terns (Sterna sandvicensis) in the presence of kleptoparasitising Black-headed Gulls (Larus ridibundus) on Griend, Dutch Wadden Sea, from 1992 to 1998. Most often, gulls robbed larger sandeels rather than herring from terns. Provided that one parent attends the chick, energy intake would be too low for the chicks' survival if exclusively fed on sandeel. By provisioning an increasing proportion of herring, parent terns could theoretically overcome a potential food shortage when the chicks grow older. However, the proportion of herring did not increase with age of chicks in most years. Instead, parents increased their foraging effort with the growth of their offspring. In years with high proportions of food loss, parents left their chicks unattended at the nest more often. In that way, parents were largely able to counterbalance food shortage of offspring. In 1992 and 1996, when diet composition was unfavorable and food losses to gulls were high, parents left their chicks unattended at the nest for ∼80% of the daylight period. It is argued that the present working level of parents might be higher than in the 1960s.

APA, Harvard, Vancouver, ISO, and other styles

35

Bradford, Rodney G., and Robert L. Stephenson. "Egg Weight, Fecundity, and Gonad Weight Variability among Northwest Atlantic Herring (Clupea harengus) Populations." Canadian Journal of Fisheries and Aquatic Sciences 49, no. 10 (October 1, 1992): 2045–54. http://dx.doi.org/10.1139/f92-227.

Full text

Abstract:

Egg weight varies among northwest Atlantic herring (Clupea harengus) populations that spawn in different seasons (n = 12), but the range in weights is less than half of that known for northeast Atlantic populations. Egg weights were similar for both spring (May–June)- and autumn (August–October)-spawning herring (1.06 ×) and most dissimilar between spring- and summer (July)-spawning herring (1.21 ×). Mean population egg weights were not correlated with temperature either at spawning or for the last 2 mo of the egg development period. The product of egg weight and fecundity (standardized to length) differed between spring- and autumn-spawning herring of the southern Gulf of St. Lawrence. Spring-spawners, particularly smaller fish [Formula: see text], have lower ripe ovary weights than do autumn-spawning herring. Differences between spawning seasons in the relative allocation of storage energy to gonad and metabolism, a process mediated by the duration of the gonad maturation period, are the likely basis for the observed patterns.

APA, Harvard, Vancouver, ISO, and other styles

36

Hebert, Craig E., J. Laird Shutt, and Ron O. Ball. "Plasma Amino Acid Concentrations as an Indicator of Protein Availability to Breeding Herring Gulls (Larus Argentatus)." Auk 119, no. 1 (January 1, 2002): 185–200. http://dx.doi.org/10.1093/auk/119.1.185.

Full text

Abstract:

Abstract In a captive-feeding study using Herring Gulls (Larus argentatus), plasma amino-acid concentrations increased in response to an increase in dietary protein. Plasma amino-acid concentrations were also measured in wild Herring Gulls captured during incubation at eight Laurentian Great Lakes colonies. Those concentrations were used as an indicator of protein availability at those locations. Significant differences in amino acid concentrations were observed among colonies. Lower amino acid levels, particularly of the essential amino acids, were measured in gulls nesting on Lake Superior, whereas values in gulls captured on Lake Ontario and Lake Erie were greater. Those geographic differences in protein availability likely reflected spatial differences in availability of high quality prey (e.g. fish). Geographic differences in prey availability probably affected diet composition. Comparison of amino-acid levels in wild birds to reference values obtained through the captive feeding study indicated that gulls nesting on Lake Superior may have been protein limited. Colony-wide estimates of adult female body condition, intraclutch variation in egg size, and productivity were correlated with an index of plasma amino-acid concentrations.

APA, Harvard, Vancouver, ISO, and other styles

37

Scopel, Lauren C., Antony W. Diamond, Stephen W. Kress, Adrian R. Hards, and Paula Shannon. "Seabird diets as bioindicators of Atlantic herring recruitment and stock size: a new tool for ecosystem-based fisheries management." Canadian Journal of Fisheries and Aquatic Sciences 75, no. 8 (August 2018): 1215–29. http://dx.doi.org/10.1139/cjfas-2017-0140.

Full text

Abstract:

Ecosystem-based fishery management requires understanding of relationships between exploited fish and their predators, such as seabirds. We used exploratory regression analyses to model relationships between Atlantic herring (Clupea harengus) in the diet of seabird chicks at nine nesting colonies in the Gulf of Maine and four types of fishery- and survey-derived herring data. We found several strong relationships, which suggests spatial structuring in herring stocks and likely patterns of herring movements before they recruit into the fishery. Some types of herring data seldom used in stock assessments — notably acoustic surveys, fixed-gear landings, and mass-at-age (i.e., weight-at-age) — correlated as strongly with seabird data as more commonly used series, such as mobile-gear landings and modeled spawning stock biomass. Seabird chick diets collected at specific locations thus offer a promising means to assess the size, distribution, and abundance of juvenile herring across a broad area prior to recruitment, which is a major source of uncertainty in fisheries. Common terns (Sterna hirundo) showed the most potential as a bioindicator, correlating well and showing consistent spatial patterns with 11 of 13 fishery data series.

APA, Harvard, Vancouver, ISO, and other styles

38

Lambert, Timothy C., and Shoukry N. Messieh. "Spawning Dynamics of Golf of St. Lawrence Herring (Clupea harengus)." Canadian Journal of Fisheries and Aquatic Sciences 46, no. 12 (December 1, 1989): 2085–94. http://dx.doi.org/10.1139/f89-258.

Full text

Abstract:

Mean day of arrival of spawning herring (Clupea harengus) in the Gulf of St. Lawrence was calculated for different length groups by region and season. During the spawning season of both spring and autumn groups, herring arrived and deposited eggs on spawning grounds in decreasing order of age and length. Spawning bed surveys at two locations confirmed batch depositions of eggs which were correlated with the presence of dominant age-classes within the spawning population. Due to limitations of the port sampling procedure for collection of biological information routinely used in herring stock assessment, some length groups were underrepresented. This could result in the underestimation of the abundance of recruiting year-classes.

APA, Harvard, Vancouver, ISO, and other styles

39

Thorne, Richard E., and G. L. Thomas. "Acoustic Observations of Gas Bubble Release by Pacific Herring (Clupea harengus pallasi)." Canadian Journal of Fisheries and Aquatic Sciences 47, no. 10 (October 1, 1990): 1920–28. http://dx.doi.org/10.1139/f90-216.

Full text

Abstract:

Evidence is given to show that Pacific herring (Clupea harengus pallasi) release gas bubbles during diel vertical migration and while holding in strong currents. The evidence includes hydroacoustic observations of echoes from both fish concentrations and gas bubbles. The fish are identified as herring on the basis of historical fisheries data and, in some cases, direct capture. Echoes from objects emanating form the fish concentrations are attributed to gas bubbles based on similarity to acoustic observations of gas bubbles in many other circumstances, as well as direct observation of bubbles at the surface in some cases. Since conclusive evidence exists that herring do not have gas secretion capability, two alternative hypotheses are presented to explain the source of the gas. One hypothesis is that the gas results from fermentation in the gut. A second is that herring gulp gas at the surface prior to descent to daytime depths. One consequence of differing amounts of gas would be changes in the acoustic target strength of herring, which is a critical parameter in acoustic assessment techniques.

APA, Harvard, Vancouver, ISO, and other styles

40

Pons, J. M., P. A. Crochet, M. Thery, and A. Bermejo. "Geographical variation in the yellow-legged gull: introgression or convergence from the herring gull?" Journal of Zoological Systematics and Evolutionary Research 42, no. 3 (August 2004): 245–56. http://dx.doi.org/10.1111/j.1439-0469.2004.00255.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

41

Delius, Juan D., and Gillian Thompson. "Brightness Dependence of Colour Preferences in Herring Gull Chicks." Zeitschrift für Tierpsychologie 27, no. 7 (April 26, 2010): 842–49. http://dx.doi.org/10.1111/j.1439-0310.1970.tb01905.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

42

Belant, Jerrold L., Thomas W. Seamans, Steven W. Gabrey, and Sheri K. Ickes. "Importance of Landfills to Nesting Herring Gulls." Condor 95, no. 4 (November 1993): 817–30. http://dx.doi.org/10.2307/1369420.

Full text

APA, Harvard, Vancouver, ISO, and other styles

43

McCleery, R. H., and R. M. Sibly. "Feeding Specialization and Preference in Herring Gulls." Journal of Animal Ecology 55, no. 1 (February 1986): 245. http://dx.doi.org/10.2307/4705.

Full text

APA, Harvard, Vancouver, ISO, and other styles

44

Gilliland, S. G., C. D. Ankney, and P. W. Hicklin. "Foraging ecology of Great Black-backed Gulls during brood-rearing in the Bay of Fundy, New Brunswick." Canadian Journal of Zoology 82, no. 9 (September 1, 2004): 1416–26. http://dx.doi.org/10.1139/z04-124.

Full text

Abstract:

We studied nesting ecology of Great Black-backed Gulls (Larus marinus L., 1758) in the Bay of Fundy, New Brunswick, in 1988 and 1989. We documented diet, feeding rate, and meal size for chicks from hatching to fledging. In 1989, colonies consisted of about 350 nests on five islands. Brood size declined with chick age, and by the end of the first week of the nestling period, 11%, 22%, 31%, and 36% of nests consisted of broods of 0, 1, 2, and 3 chicks, respectively. Average meals size increased and feeding frequency declined slightly with chick age. We estimated that 619.6 kg (dry mass) of food was fed to chicks during the nestling period in 1989. The composition of the chicks' diet changed with age and was most varied early in the nestling period, when they were fed relatively equal proportions of major food types. Overall, Atlantic herring (Clupea harengus L., 1758) was the most important prey item and contributed 63% of the energy consumed by chicks during the nestling period. Northern krill (Meganyctiphanes norvegica (M. Sars, 1857); 11.9%), lumpfish (Cyclopterus lumpus L., 1758; 10.4%), and waste (fisheries and domestic; 4.7%) were also important foods. Gull chicks and Common Eider (Somateria mollissima (L., 1758)) ducklings made up 1.9% and 0.8%, respectively, of the chicks' energy budget. We conclude that the primary factor effecting productivity of the Great Black-backed Gull was food availability, and the amount of food available varied little over the nesting period in 1989.

APA, Harvard, Vancouver, ISO, and other styles

45

Alessandro, David, Julie Dollinger, John D. Gordon, Susan K. Mariscal, and James L. Gould. "The ontogeny of the pecking response of herring gull chicks." Animal Behaviour 37 (March 1989): 372–82. http://dx.doi.org/10.1016/0003-3472(89)90085-7.

Full text

APA, Harvard, Vancouver, ISO, and other styles

46

Brown, R. G. B. "SPECIES ISOLATION BETWEEN THE HERRING GULL LARUS ARGENTATUS AND LESSER BUCK-BACKED GULL L. FUSCUS." Ibis 109, no. 3 (April 3, 2008): 310–17. http://dx.doi.org/10.1111/j.1474-919x.1967.tb04005.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

47

Rosen, David AS, and Andrew W. Trites. "Pollock and the decline of Steller sea lions: testing the junk-food hypothesis." Canadian Journal of Zoology 78, no. 7 (July 1, 2000): 1243–50. http://dx.doi.org/10.1139/z00-060.

Full text

Abstract:

The decline of Steller sea lions (Eumetopias jubatus) in the Gulf of Alaska and the Aleutian Islands may be the result of them eating too much pollock (a gadid fish) instead of a more balanced and diverse diet containing fattier fishes, such as herring or sandlance. We sought to test this junk-food hypothesis by feeding six captive Steller sea lions (ages 0.9-4.5 years) only pollock or herring. All sea lions gained mass while eating herring. However, eating only pollock for short periods (11-23 d) caused the study animals to lose an average of 6.5% of their initial body mass (0.6 kg/d) over an average feeding trial of 16 d (initial mass averaged 125 kg). The animals were allowed to eat as much pollock as they wanted but did not increase their food intake to compensate for the low energy they were receiving. The sea lions showed progressive metabolic depression while losing body mass on a pollock-only diet. The loss of body mass while eating pollock was due to the lower gross energy content of pollock versus herring, the higher cost of digesting pollock, and the increased energy loss from digesting the larger quantity of fish needed to compensate for the lower energy content of pollock. Thus, our sea lions would have had to eat 35-80% more pollock than herring to maintain similar net energy intakes. Results from our captive-feeding studies are consistent with the junk-food hypothesis and have serious implications for Steller sea lions that have been eating primarily pollock in the Gulf of Alaska and the Aleutian Islands.

APA, Harvard, Vancouver, ISO, and other styles

48

Graves, J., A. Whiten, and S. P. Henzi. "Parent-Offspring Conflict over Independence in the Herring Gull (Larus argentatus)." Ethology 88, no. 1 (April 26, 2010): 20–34. http://dx.doi.org/10.1111/j.1439-0310.1991.tb00260.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

Parsons, Jasper. "EGG SIZE, LAYING DATE AND INCUBATION PERIOD IN THE HERRING GULL." Ibis 114, no. 4 (April 3, 2008): 536–41. http://dx.doi.org/10.1111/j.1474-919x.1972.tb00855.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

Parsons, Jasper. "ASYNCHRONOUS HATCHING AND CHICK MORTALITY IN THE HERRING GULL LARUS ARGENTATUS." Ibis 117, no. 4 (April 3, 2008): 517–20. http://dx.doi.org/10.1111/j.1474-919x.1975.tb04247.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Herring gull behaviour'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles