Habitat selection and foraging site fidelity in Caspian Terns (Hydroprogne caspia) breeding in the Baltic Sea

Habitat preferences and foraging strategies affect population-level space use and are therefore crucial to understanding population change and implementing spatial conservation and management actions. We investigated the breeding season habitat preference and foraging site fidelity of the under-studied and threatened, Baltic Sea population of Caspian Terns (Hydroprogne caspia). Using GPS devices, we tracked 20 adult individuals at two breeding colonies, in Sweden and Finland, from late incubation through chick-rearing. Analyzing foraging movements during this period, we describe trip characteristics for each colony, daily metrics of effort, habitat use, and foraging site fidelity. We found that daily time spent away from the colony increased throughout the season, with colony-level differences in terms of distance travelled per day. In general, terns selected shallow waters between 0–5 meters in depth with certain individuals using inland lakes for foraging. We show, for the first time, that individual Caspian Terns are faithful to foraging sites throughout the breeding season, and that individuals are highly repeatable in their strategies regarding foraging site fidelity. These results fill important knowledge gaps for this at-risk population, and extend our general knowledge of the breeding season foraging ecology of this widespread species.

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Effects of age and reproductive status on individual foraging site fidelity in a long-lived marine predator

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2017.1068 ◽

2017 ◽

Vol 284 (1859) ◽

pp. 20171068 ◽

Cited By ~ 41

Author(s):

Stephen C. Votier ◽

Annette L. Fayet ◽

Stuart Bearhop ◽

Thomas W. Bodey ◽

Bethany L. Clark ◽

...

Keyword(s):

Site Fidelity ◽

Foraging Strategies ◽

Common Component ◽

Small Component ◽

Phenotypic Differences ◽

Marine Predator ◽

Global Positioning ◽

Foraging Site ◽

Foraging Ability ◽

Foraging Specialization

Individual foraging specializations, where individuals use a small component of the population niche width, are widespread in nature with important ecological and evolutionary implications. In long-lived animals, foraging ability develops with age, but we know little about the ontogeny of individuality in foraging. Here we use precision global positioning system (GPS) loggers to examine how individual foraging site fidelity (IFSF), a common component of foraging specialization, varies between breeders, failed breeders and immatures in a long-lived marine predator—the northern gannet Morus bassanus . Breeders (aged 5+) showed strong IFSF: they had similar routes and were faithful to distal points during successive trips. However, centrally placed immatures (aged 2–3) were far more exploratory and lacked route or foraging site fidelity. Failed breeders were intermediate: some with strong fidelity, others being more exploratory. Individual foraging specializations were previously thought to arise as a function of heritable phenotypic differences or via social transmission. Our results instead suggest a third alternative—in long-lived species foraging sites are learned during exploratory behaviours early in life, which become canalized with age and experience, and refined where possible—the exploration-refinement foraging hypothesis. We speculate similar patterns may be present in other long-lived species and moreover that long periods of immaturity may be a consequence of such memory-based individual foraging strategies.

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Foraging site fidelity and stable isotope values of loggerhead turtles tracked in the Gulf of Mexico and northwest Caribbean

Marine Ecology Progress Series ◽

10.3354/meps10655 ◽

2014 ◽

Vol 502 ◽

pp. 267-279 ◽

Cited By ~ 34

Author(s):

AD Tucker ◽

BD MacDonald ◽

JA Seminoff

Keyword(s):

Stable Isotope ◽

Gulf Of Mexico ◽

Site Fidelity ◽

Loggerhead Turtles ◽

Foraging Site

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Long-term individual foraging site fidelity—why some gannets don't change their spots

Ecology ◽

10.1890/14-1300.1 ◽

2015 ◽

Vol 96 (11) ◽

pp. 3058-3074 ◽

Cited By ~ 72

Author(s):

Ewan D. Wakefield ◽

Ian R. Cleasby ◽

Stuart Bearhop ◽

Thomas W. Bodey ◽

Rachel D. Davies ◽

...

Keyword(s):

Site Fidelity ◽

Foraging Site

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NOTES ON THE ECOLOGY OF THE COLOMBIAN LEAFTOED GECKO (PHYLLODACTYLUS TRANSVERSALIS), ENDEMIC TO MALPELO ISLAND

Bulletin of Marine and Coastal Research ◽

10.25268/bimc.invemar.2013.42.2.54 ◽

2016 ◽

Vol 42 (2) ◽

Author(s):

Mateo López Victoria ◽

Matthias Jurczyk ◽

Volkmar Wolters

Keyword(s):

Population Size ◽

Breeding Season ◽

Habitat Preference ◽

Habitat Preferences ◽

Original Description ◽

Tropical Pacific ◽

Reference Points ◽

Eastern Tropical Pacific ◽

Reptile Species ◽

Malpelo Island

The Colombian leaf-toed gecko (Phyllodactylus transversalis) is the least known reptile species of Malpelo Island (Eastern Tropical Pacific). In the 37 years since its original description, no single study strictly dedicated to this species has been conducted. With the goal of providing information on the ecology and population size of this gecko, data collected during two visits to the island are presented. Behavior and reproduction were studied by following individuals during the night and by searching for hidden individuals and eggs during the day. Population’s density and habitat preferences were estimated by classifying the island’s surfaces into four types and counting geckos inside those habitats within band transects. General morphological measurements of geckos were performed as reference points for future comparisons. Phyllodactylus transversalis lays its eggs in narrow crevices of rocks, apparently communally. Reproduction seems to take place during most of the year, probably associated with the peak breeding season of seabirds. Although conspecifics shared shelters during the day, densities during the night suggest no apparent habitat preference for foraging. Population size of this species was estimated at approximately 114000 individuals.

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Temporal Variation in Breeding Season Survival and Cause-Specific Mortality of Lesser Prairie-Chickens

Journal of Fish and Wildlife Management ◽

10.3996/112016-jfwm-081 ◽

2018 ◽

Vol 9 (2) ◽

pp. 507-518

Author(s):

Andrew R. Meyers ◽

Scott A. Carleton ◽

William R. Gould ◽

Clay T. Nichols ◽

David A. Haukos ◽

...

Keyword(s):

New Mexico ◽

Breeding Season ◽

Late Summer ◽

Male And Female ◽

Brood Rearing ◽

Management Actions ◽

Specific Mortality ◽

Prairie Chicken ◽

Female Survival ◽

Similar Survival

Abstract The lesser prairie-chicken Tympanuchus pallidicinctus has experienced significant declines in distribution and abundance since the early 1900s. A severe and prolonged drought from 2009 to 2013 resulted in further declines in population numbers and despite improved environmental and habitat conditions since 2013, populations of lesser prairie chickens have shown little improvement. To investigate whether breeding season survival of lesser prairie-chickens in eastern New Mexico could be driving this response, we developed the following objectives: 1) estimate male and female breeding-season survival; 2) determine whether male and female survival varies temporally among lekking, nesting, and brood-rearing periods; and 3) determine cause-specific mortality during the breeding season. We captured and radiocollared 76 lesser prairie-chickens (50 male, 26 female) during spring of 2014 and 2015 and estimated their survival throughout the breeding season (15 March–31 August). Male survival was nearly double that of females in both years (0.79–0.81 and 0.38–0.45, respectively). Males had similar survival across all periods (lekking, postlekking, late summer: 0.89–0.95). Females had the greatest period-specific survival during lekking and brood rearing (0.87 ± 0.08 and 0.85 ± 0.10, respectively) relative to the nesting period (0.58 ± 0.11). Mammalian predation was the primary cause of mortality in both years. Our results indicate that in New Mexico 1) lesser prairie-chicken breeding season survival was consistent with geographically similar studies, 2) females have lower survival during the nesting period, and 3) female lesser prairie-chicken survival was lower than male survival regardless of time period. Management actions that provide and protect high-quality nesting habitat may help ensure that female survival is maximized during the nesting period.

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An ecosystem model of food web and fisheries interactions in the Baltic Sea

ICES Journal of Marine Science ◽

10.1016/s1054-3139(03)00098-5 ◽

2003 ◽

Vol 60 (5) ◽

pp. 939-950 ◽

Cited By ~ 89

Author(s):

Chris J Harvey ◽

Sean P Cox ◽

Timothy E Essington ◽

Sture Hansson ◽

James F Kitchell

Keyword(s):

Baltic Sea ◽

Food Web ◽

Species Interactions ◽

Gadus Morhua ◽

Population Analysis ◽

Clupea Harengus ◽

Trophic Relationships ◽

The Baltic Sea ◽

Management Actions ◽

The Baltic

Abstract Because fisheries operate within a complex array of species interactions, scientists increasingly recommend multispecies approaches to fisheries management. We created a food web model for the Baltic Sea proper, using the Ecopath with Ecosim software, to evaluate interactions between fisheries and the food web from 1974 to 2000. The model was based largely on values generated by multispecies virtual population analysis (MSVPA). Ecosim outputs closely reproduced MSVPA biomass estimates and catch data for sprat (Sprattus sprattus), herring (Clupea harengus), and cod (Gadus morhua), but only after making adjustments to cod recruitment, to vulnerability to predation of specific species, and to foraging times. Among the necessary adjustments were divergent trophic relationships between cod and clupeids: cod exhibited top-down control on sprat biomass, but had little influence on herring. Fishing, the chief source of mortality for cod and herring, and cod reproduction, as driven by oceanographic conditions as well as unexplained variability, were also key structuring forces. The model generated many hypotheses about relationships between key biota in the Baltic Sea food web and may ultimately provide a basis for estimating community responses to management actions.

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There’s no place like home — site fidelity by female moose (Alces alces) in central Ontario, Canada

Canadian Journal of Zoology ◽

10.1139/cjz-2021-0010 ◽

2021 ◽

pp. 557-563

Author(s):

A.A.D. McLaren ◽

B.R. Patterson

Keyword(s):

Global Positioning System ◽

Site Fidelity ◽

Habitat Management ◽

Alces Alces ◽

Spatial Scales ◽

Management Actions ◽

Global Positioning ◽

Protective Cover ◽

System Data ◽

Provincial Park

Site fidelity is thought to provide increased fitness through familiarity with the distribution of forage, protective cover, breeding and offspring rearing sites, and predators. For moose (Alces alces (Linnaeus, 1758)), previous research has documented fidelity at varying spatial scales. Our objective was to build on this knowledge and assess fidelity by adult female moose in two areas of central Ontario, Canada (Algonquin Provincial Park (APP) and Wildlife Management Unit 49 (WMU49)). We used global positioning system data to generate mean weekly locations for collared moose, then measured the distance between paired weekly locations among consecutive years to evaluate site fidelity. We tested for effects of study area, biological season, moose age, and reproductive status using generalized linear mixed models. Moose demonstrated stronger site fidelity in WMU49, an area with more anthropogenic disturbance, than the protected area, APP. Fidelity was weakest in the winter, but was similar among other seasons and was independent of maternal age and the presence of a calf. Our study highlights the need to consider the scale of site fidelity relative to habitat management. Actions aimed at supporting moose populations might benefit more by protecting habitat classes selected by moose rather than specific sites used by individuals.

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Evaluating impacts of bottom trawling and hypoxia on benthic communities at the local, habitat, and regional scale using a modelling approach

ICES Journal of Marine Science ◽

10.1093/icesjms/fsz219 ◽

2019 ◽

Vol 77 (1) ◽

pp. 278-289 ◽

Cited By ~ 1

Author(s):

P D van Denderen ◽

S G Bolam ◽

R Friedland ◽

J G Hiddink ◽

K Norén ◽

...

Keyword(s):

Baltic Sea ◽

Spatial Scales ◽

Benthic Communities ◽

Regional Scale ◽

The Baltic Sea ◽

Benthic Habitats ◽

Bottom Trawling ◽

Management Actions ◽

The Baltic ◽

Local Habitat

Abstract Bottom trawling disturbance and hypoxia are affecting marine benthic habitats worldwide. We present an approach to predict their effects on benthic communities, and use the approach to estimate the state, the biomass relative to carrying capacity, of the Baltic Sea at the local, habitat, and regional scale. Responses to both pressures are expected to depend on the longevity of fauna, which is predicted from benthic data from 1558 locations. We find that communities in low-salinity regions mostly consist of short-lived species, which are, in our model, more resilient than those of the saline areas. The model predicts that in 14% of the Baltic Sea region benthic biomass is reduced by at least 50%, whereas an additional 8% of the region has reductions of 10–50%. The effects of hypoxia occur over larger spatial scales and lead to a low state of especially deep habitats. The approach is based on a simple characterization of the benthic community, which comes with high uncertainty, but allows for the identification of benthic habitats that are at greatest risk and prioritization of management actions at the regional scale. This information supports the development of sustainable approaches to manage impact of human activities on benthic ecosystems.

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