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- Data packageData from: Coexistence of two sympatric predators in a transitional ecosystem under constraining environmental conditions: a perspective from space and habitat use(2023-12-11) Warret Rodrigues, Chloé; Roth, James D.Background: Range expansion of species, a major consequence of climate changes, may alter communities substantially due to competition between expanding and native species. Methods: We first quantified size differences between an expanding habitat generalist, the red fox (Vulpes vulpes), and a circumpolar habitat specialist, the Arctic foxes (Vulpes lagopus), at the edge of the Arctic, where climate-related changes occur rapidly, to predict the likelihood of the larger competitor escalating interference to intraguild killing. We then used satellite telemetry to evaluate competition in a heterogeneous landscape by examining space use early during the foxes' reproductive period, when resource scarcity, increased-food requirements and spatial constraints likely exacerbate the potential for interference. We used time-LoCoH to quantify space and habitat use, and Minta's index to quantify spatio-temporal interactions between neighbors. Results: Our morphometric comparison involving 236 foxes found that the potential for escalated interference between these species was high due to intermediate size difference. However, our results from 17 collared foxes suggested that expanding and native competitors may coexist when expanding species occur at low densities. Low home-range overlap between neighbors suggested territoriality and substantial exploitation competition for space. No obvious differential use of areas shared by heterospecific neighbors suggested low interference. If anything, intraspecific competition between red foxes may be stronger than interspecific competition. Red and Arctic foxes used habitat differentially, with near-exclusive use of forest patches by red foxes and marine habitats by Arctic foxes. Conclusion: Heterogeneous landscapes may relax interspecific competition between expanding and native species, allowing exclusive use of some resources. Furthermore, the scarcity of habitats favored by expanding species may emphasize intraspecific competition between newcomers over interspecific competition, thus creating the potential for self-limitation of expanding populations. Dominant expanding competitors may benefit from interference, but usually lack adaptations to abiotic conditions at their expansion front, favoring rear-edge subordinate species in exploitation competition. However, due to ongoing climate change, systems are usually not at equilibrium. A spread of habitats and resources favorable to expanding species may promote higher densities of antagonistically dominant newcomers, which may lead to extirpation of native species.
- Data packageData from: Deployment details for satellite tags deployed on Antarctic blue whales during the Antarctic blue whale voyage 2013, Ver. 2(2022-11-07) Andrews-Goff, Virginia; Bell, Elanor M.; Miller, Brian S.; Wotherspoon, Simon J.; Double, Michael C.One aim of the Antarctic blue whale voyage was to attempt to deploy satellite tags on Antarctic blue whales in order to describe their movement and behaviour. This was the first time satellite tags had ever been deployed on Antarctic blue whales. Antarctic blue whale movement has been described using static location information such as that derived from the retrieval of a discovery-tagged whales, photo identification or acoustic data. These techniques however are unable to provide a continuous record of actual movements instead inferring movement from two (or more) known locations at two (or more) separate points in time. Actual movements of the whale between these points in time are not known. As such, detailed information such as large scale migratory movement between breeding and feeding grounds or even fine scale movement within a feeding ground remain poorly understood.
- Data packageData from: Re-colonization by common eiders (Somateria mollissima) in the Aleutian Archipelago following removal of introduced arctic foxes (Vulpes lagopus)(2015-05-19) Petersen, Margaret R.; Byrd, G. Vernon; Sonsthagen, Sarah A.; Sexon, Matthew G.Islands provide refuges for populations of many species where they find safety from predators, but the introduction of predators frequently results in elimination or dramatic reductions in island-dwelling organisms. When predators are removed, re-colonization for some species occurs naturally, and inter-island phylogeographic relationships and current movement patterns can illuminate processes of colonization. We studied a case of re-colonization of common eiders (Somateria mollissima) following removal of introduced arctic foxes (Vulpes lagopus) in the Aleutian Archipelago, Alaska. We expected common eiders to resume nesting on islands cleared of foxes and to re-colonize from nearby islets, islands, and island groups. We thus expected common eiders to show limited genetic structure indicative of extensive mixing among island populations. Satellite telemetry was used to record current movement patterns of female common eiders from six islands across three island groups. We collected genetic data from these and other nesting common eiders at 14 microsatellite loci and the mitochondrial DNA control region to examine population genetic structure, historical fluctuations in population demography, and gene flow. Our results suggest recent interchange among islands. Analysis of microsatellite data supports satellite telemetry data of increased dispersal of common eiders to nearby areas and little between island groups. Although evidence from mtDNA is suggestive of female dispersal among island groups, gene flow is insufficient to account for recolonization and rapid population growth. Instead, near-by remnant populations of common eiders contributed substantially to population expansion, without which re-colonization would have likely occurred at a much lower rate. Genetic and morphometric data of common eiders within one island group two and three decades after re-colonization suggests reduced movement of eiders among islands and little movement between island groups after populations were re-established. We predict that re-colonization of an island group where all common eiders are extirpated could take decades.
- Data packageData from: Study "MPIAB Argos white stork tracking (1991-2017)"(2022-12-26) Berthold, Peter; Kaatz, Christoph; Kaatz, Michael; Querner, Ulrich; van den Bossche, Willem; Chernetsov, Nikita; Fiedler, Wolfgang; Wikelski, MartinSatellite tracking of white storks (Ciconia ciconia) was begun by the Max Planck Institute of Ornithology and collaborators in 1991. After solar-powered transmitters became available in 1995, extended battery life combined with the possibility to replace transmitters over time allowed monitoring the movements of individual storks across multiple migration seasons, with one individual, Prinzesschen, tracked for over a decade. Research efforts continue using primarily GSM-based tracking technologies. This dataset includes over 200 storks tagged in Belgium, Germany, Greece, Israel, Poland, Russia, South Africa, Spain and Switzerland. As noted in the deployment information, some movements are influenced by experimental manipulations. This long-term study confirms what previous several-year tracking studies of white storks had indicated: there can be great variability from year to year in the choice of winter quarters as well as in the routes and times of migration, intermediate destinations and stop-over periods, but constancy of winter quarters and migration routes is also possible. The variability may well be caused by external factors, of which food supply is probably predominant.
- Data packageData from: Study "Arctic hare Alert - Argos tracking"(2021-12-31) Berteaux, DominiqueLagomorphs (pikas, rabbits and hares) are small to medium-sized herbivores that occupy diverse habitats across all continents except Antarctica. Lagomorph movements are usually limited to natal dispersal, performed over relatively short distances (< 1 to 35 km). Here, we report the longest travel ever documented in a lagomorph, an Arctic hare Lepus arcticus, tracked during a project characterizing large-scale movements in the Canadian High Arctic using Argos satellite telemetry. From her Alert departure to her settlement near Lake Hazen, she traveled a minimum cumulative distance of 388 km over 49 days. This long-distance movement reveals unprecedented mobility capacities in this mammalian order.
- Data packageData from: Australia’s east coast humpback whales: satellite tag derived movements on breeding grounds, feeding grounds and along the northern and southern migration.(2023-12-12) Andrews-Goff, Virginia; Gales, Nick; Childerhouse, Simon J.; Laverick, Sarah M.; Polanowski, Andrea M.; Double, Michael C.Background: Satellite tags were deployed on 50 east Australian humpback whales (breeding stock E1) between 2008 and 2010 on their southward migration, northward migration and feeding grounds in order to identify and describe migratory pathways, feeding grounds and possible calving areas. At the time, these movements were not well understood and calving grounds were not clearly identified. To the best of our knowledge, this dataset details all long-term, implantable tag deployments that have occurred to date on breeding stock E1. As such, these data provide researchers, regulators and industry with clear and valuable insights into the spatial and temporal nature of humpback whale movements along the eastern coastline of Australia and into the Southern Ocean. As this population of humpback whales navigates an increasingly complex habitat undergoing various development pressures and anthropogenic disturbances, in addition to climate-mediated changes in their marine environment, this dataset may also provide a valuable baseline. New information: At the time these tracks were generated, these were the first satellite tag deployments intended to deliver long-term, detailed movement information on east Australian (breeding stock E1) humpback whales. The tracking data revealed previously unknown migratory pathways into the Southern Ocean, with 11 individuals tracked to their Antarctic feeding grounds. Once assumed to head directly south on their southern migration, five individuals initially travelled west towards New Zealand. Six tracks detailed the coastal movement of humpback whales migrating south. One tag transmitted a partial southern migration, then ceased transmissions only to begin transmitting eight months later as the animal was migrating north. Northern migration to breeding grounds was detailed for 13 individuals, with four tracks including turning points and partial southern migrations. Another 14 humpback whales were tagged in Antarctica, providing detailed Antarctic feeding ground movements. Broadly speaking, the tracking data revealed a pattern of movement where whales were at their northern limit in July and their southern limit in March. Migration north was most rapid across the months of May and June, whilst migration south was most rapid between November and December. Tagged humpback whales were located on their Antarctic feeding grounds predominantly between January and May and approached their breeding grounds between July and August. Tracking distances ranged from 68 km to 8580 km and 1 to 286 days. To the best of our knowledge, this dataset compiles all of the long-term tag deployments that have occurred to date on breeding stock E1.
- Data packageData from: Study "Herring Gulls (Larus Argentatus); Ronconi; Kent Island, Canada"(2020-06-17) Ronconi, Robert A.; Shlepr, Katherine R.Background: Recent studies have proposed that birds migrating short distances migrate at an overall slower pace, minimizing energy expenditure, while birds migrating long distances minimize time spent on migration to cope with seasonal changes in environmental conditions. Methods: We evaluated variability in the migration strategies of Herring Gulls (Larus argentatus), a generalist species with flexible foraging and flight behaviour. We tracked one population of long distance migrants and three populations of short distance migrants, and compared the directness of their migration routes, their overall migration speed, their travel speed, and their use of stopovers. Results: Our research revealed that Herring Gulls breeding in the eastern Arctic migrate long distances to spend the winter in the Gulf of Mexico, traveling more than four times farther than gulls from Atlantic Canada during autumn migration. While all populations used indirect routes, the long distance migrants were the least direct. We found that regardless of the distance the population traveled, Herring Gulls migrated at a slower overall migration speed than predicted by Optimal Migration Theory, but the long distance migrants had higher speeds on travel days. While long distance migrants used more stopover days overall, relative to the distance travelled all four populations used a similar number of stopover days. Conclusions: When taken in context with other studies, we expect that the migration strategies of flexible generalist species like Herring Gulls may be more influenced by habitat and food resources than migration distance.
- Data packageData from: Space use by Swainson's hawk (Buteo swainsoni) in the Natomas Basin, California(2017-05-05) Fleishman, Erica; Anderson, Jesse; Dickson, Brett G.; Krolick, David; Estep, Jim A.; Anderson, Richard L.; Elphick, Chris S.; Dobkin, David S.; Bell, Doug A.We used satellite-based remote sensing to estimate home ranges for Swainson’s Hawk, a species listed as threatened in California (USA), on its breeding grounds in the Natomas Basin (northern Central Valley, California) and to evaluate whether the species’ space-use intensity (statistically derived density of telemetry locations) was associated with land cover, sex, reproductive success, or life stage of offspring. We differentiated seven classes of land cover—alfalfa, annually rotated irrigated crops, developed, grassland, orchard / vineyard, rice, and water. From 2011–2013, we fitted transmitters with global positioning systems to 23 adult Swainson’s Hawks. We recorded a minimum of six locations per day per bird from spring through early autumn of each year. We used a fixed, bivariate-normal kernel estimator to calculate a utilization distribution at 30-m resolution for each life stage of each individual within each year. We used a linear mixed model to estimate the associations between intensity of space use and land cover, sex, and reproductive status. The majority of adult Swainson’s Hawks traveled distances up to 8–10 km from the nest throughout the breeding season. Median seasonal home-range sizes in a given year ranged from 87–172 km2. The association between intensity of space use and grassland was 50–139% stronger, and the association between intensity of space use and alfalfa 23–59% stronger, than the associations between intensity of space use and any other land-cover type. Intensity of space use did not vary as a function of sex, reproductive status, or life stage. Given our results and additional knowledge of the species’ ecology, we suggest that reproductive success and, in turn, population-level recruitment may be associated equally if not more closely with availability of nesting sites than with the current distribution of land cover.
- Data packageData from: Study "Satellite tracking of black-capped petrels, 2019"(2023-05-30) Satgé, Yvan G.; Keitt, Bradford S.; Gaskin, Chris P.; Patteson, J. Brian; Jodice, Patrick G.R.
- Data packageData from: Study "Arctic fox Bylot - Argos tracking"(2021-12-30) Berteaux, DominiqueRapid range expansion of boreal forest predators onto the tundra may disrupt local ecological processes, notably through competition with ecologically similar species. Red foxes (Vulpes vulpes) have expanded their range northwards throughout the Canadian Arctic, inducing competition with endemic Arctic foxes (V. lagopus). We studied competition between Arctic and red foxes, with a focus on interference competition, and winter movements of red foxes using satellite telemetry and den occupancy data from both species. We worked at Bylot Island (Nunavut) and Herschel Island (northern Yukon), two sites at the northern limit of the red fox’s range. As expected, red fox home ranges were 56% larger on average than Arctic fox home ranges. However, red foxes did not exclude arctic foxes regionally nor did they prevent them from breeding successfully in their vicinity. On Bylot Island, Arctic foxes did not spatially avoid red foxes more than their conspecifics, as evidenced by similar intra- and inter-specific home-range overlaps. On Herschel Island, the red fox pair's home range extensively overlapped the home range of their Arctic fox neighbors. While red foxes tracked on Bylot Island survived several winters without expanding or leaving their home ranges, those on Herschel Island moved onto the sea ice and died. Overall, our results demonstrate low levels of interference competition between the two species in the High Canadian Arctic. When red fox density is low, as in our study areas where land protection prevents predator subsidization by anthropogenic food sources, Arctic and red foxes may be able to co-exist with limited antagonistic interactions. Our sample sizes were limited by the naturally low density of red foxes at their northernmost edge, thus replication is needed to fully understand winter space use and intraguild interactions in this species at its northern range limit.