scholarly journals Reactions of Narwhals, Monodon monoceros, to Killer Whale, Orcinus orca, Attacks in the Eastern Canadian Arctic

2006 ◽  
Vol 120 (4) ◽  
pp. 457 ◽  
Author(s):  
Kristin L. Laidre ◽  
Mads Peter Heide-Jørgensen ◽  
Jack R. Orr
Keyword(s):  
Killer Whale ◽  
Satellite Telemetry ◽  
Behavioral Responses ◽  
Space Use ◽  
High Arctic ◽  
Behavioral Changes ◽  
Home Ranges ◽  
Observation Data ◽  
Killer Whales ◽  
Time Changes

A Killer Whale attack on Narwhals was observed at Kakiak Point in Admiralty Inlet, Nunavut, Canada, in August 2005. Behavioral responses of both Narwhals and Killer Whales were documented by direct observation. Data collected from Narwhals instrumented with satellite-linked transmitters 5 days prior to the arrival of Killer Whales were used to examine changes in Narwhal movement patterns (e.g., dispersal and clumping) five days before the attack, during the attack, and five days after Killer Whales left the area. A minimum of four Narwhals were killed by 12-15 Killer Whales in a period of 6 hours. Narwhals showed a suite of behavioral changes in the immediate presence of Killer Whales including slow, quiet movements, travel close to the beach (<2 m from shore), use of very shallow water, and formation of tight groups at the surface. These behavioral changes are consistent with Inuit accounts of Killer Whale attacks on Narwhals. During the attack, Narwhals dispersed broadly, the groups were less clumped (standard deviation of inter-whale mean latitudes and longitudes), Narwhal space-use doubled from pre-attack home ranges of 347 km2 to 767 km2 (kernel 50% probability), and Narwhals shifted their distribution further south of the attack site. After the disappearance of Killer Whales, north-south dispersal of Narwhals contracted and was similar to pre-attack levels, total space use decreased slightly (599 km2), yet west-east dispersal remained high. Narwhals were distributed significantly (P < 0.001) more broadly offshore in areas not used before the occurrence of Killer Whales. In general, short-term reactions of Narwhals to Killer Whale presence were obvious; yet normal behavior (as observed from shore) resumed shortly after Killer Whales left the area. Long-term (five day) Narwhal behavioral responses included increased dispersal of Narwhal groups over large offshore areas. This is among the few reports of eyewitness Killer Whale attacks on Narwhals in the high Arctic and is the first time changes in Narwhal behavior have been documented in response to a predation event through the use of satellite telemetry.

Behavioral responses of coyotes to wolf recolonization in northwestern Montana

1999 ◽  
Vol 77 (12) ◽  
pp. 1919-1927 ◽  
Author(s):  
Wendy M Arjo ◽  
Daniel H Pletscher
Keyword(s):  
Canis Lupus ◽  
Behavioral Responses ◽  
Behavioral Changes ◽  
Home Ranges ◽  
Wolf Population ◽  
Temporal Separation ◽  
Temporal Partitioning ◽  
Northwestern Montana ◽  
Range Overlap ◽  
Overlap Area

Recent recolonization of northwestern Montana by wolves (Canis lupus) provided an opportunity to examine behavioral responses of coyotes (Canis latrans) to a reestablished wolf population. Coyote and wolf annual home ranges overlapped extensively; however, seasonal overlap was not as pronounced. Most seasonal coyote home ranges were located between wolf packs or along the edge of wolf territories, but wolves and coyotes did not use the seasonal overlap area differently than expected. Most of the coyotes maintained random separation distances from wolves, though three coyotes were closer to wolves than expected. No difference in summer activity was found between the canids; however, temporal partitioning occurred during the winter, which may have allowed the increase in home-range overlap observed during the winter. Additionally, temporal partitioning occurred through differential arrangement of canid home ranges (i.e., wolf home ranges were smaller in summer) and reduced overlap of seasonal home ranges. Coyotes were usually singletons and some pairs, and before wolf colonization they fed on lagomorphs and plants. After wolf colonization, coyotes tended to be in pairs and small packs and they relied on ungulates. Although we documented wolves killing coyotes, coyotes are coexisting with wolves through spatial and temporal separation and behavioral changes.

scholarly journals Space use of wintering waterbirds in India: Influence of trophic ecology on home-range size

2014 ◽  
Vol 60 (5) ◽  
pp. 616-621
Author(s):  
Tsewang Namgail ◽  
John Y. Takekawa ◽  
Sivananinthaperumal Bala-Chandran ◽  
Ponnusamy Sathiyaselvam ◽  
Taej Mundkur ◽  
...  
Keyword(s):  
Home Range ◽  
Body Mass ◽  
Feeding Habits ◽  
Satellite Telemetry ◽  
Space Use ◽  
Home Range Size ◽  
Range Size ◽  
Home Ranges ◽  
Biological Traits ◽  
Indian States

Abstract Relationship between species’ home range and their other biological traits remains poorly understood, especially in migratory birds due to the difficulty associated with tracking them. Advances in satellite telemetry and remote sensing techniques have proved instrumental in overcoming such challenges. We studied the space use of migratory ducks through satellite telemetry with an objective of understanding the influence of body mass and feeding habits on their home-range sizes. We marked 26 individuals, representing five species of migratory ducks, with satellite transmitters during two consecutive winters in three Indian states. We used kernel methods to estimate home ranges and core use areas of these waterfowl, and assessed the influence of body mass and feeding habits on home-range size. Feeding habits influenced the home-range size of the migratory ducks. Carnivorous ducks had the largest home ranges, herbivorous ducks the smallest, while omnivorous species had intermediate home-ranges. Body mass did not explain variation in home-range size. To our knowledge, this is the first study of its kind on migratory ducks, and it has important implications for their conservation and management.

scholarly journals Effects of Visitor Presence and Crowd Size on Zoo-Housed Red Kangaroos (Macropus Rufus) During and After a COVID-19 Closure

2021 ◽  
Vol 8 (4) ◽  
pp. 521-537
Author(s):  
Megan Jones ◽  
Kylen N. Gartland ◽  
Grace Fuller
Keyword(s):  
Behavioral Responses ◽  
Space Use ◽  
Common Species ◽  
Behavioral Changes ◽  
Social Proximity ◽  
Close Proximity ◽  
Macropus Rufus ◽  
Crowd Size ◽  
Time Spent Feeding ◽  
Better Than

Macropods, particularly kangaroos and wallabies, are common species included in walk-through habitats that put them in close proximity to zoo visitors. However, there has been little research into how visitor presence and density impact the welfare of these individuals. We monitored the behavior and space use of fifteen red kangaroos (Macropus rufus) for a total of ten weeks during and after a nearly three-month zoo closure due to the COVID-19 pandemic. Our findings revealed potential visitor effects, evidenced by more time spent in social proximity, greater inactivity, and more restricted space use after the zoo reopened. Although temperature and weather likely played a role in at least some of these behavioral changes, social proximity and space use changed with crowd size in a manner consistent with our zoo status (i.e., open or closed) results. Additionally, time spent feeding was significantly related to crowd size but not zoo status, such that the kangaroos spent more time feeding when there were no visitors in the habitat. These findings suggest that visitor effects explain these behavioral changes better than seasonal confounds. We also noted several individual differences in response to visitor presence and crowd size, highlighting the importance of evaluating behavioral responses to visitors on an individual basis.

scholarly journals Differences in movement and dynamic resource selection between breeders and floaters revealed with an Ornstein-Uhlenbeck space use model

2020 ◽  
Author(s):  
Joseph M. Eisaguirre ◽  
Travis L. Booms ◽  
Christopher P. Barger ◽  
Stephen B. Lewis ◽  
Greg A. Breed
Keyword(s):  
Population Ecology ◽  
Resource Selection ◽  
Large Fraction ◽  
Conservation Status ◽  
Satellite Telemetry ◽  
Space Use ◽  
Breeding Population ◽  
Central Place ◽  
Home Ranges ◽  
Breeding Seasons

AbstractIn populations of many taxa, a large fraction of sexually mature individuals do not breed but are attempting to enter the breeding population. Such individuals, often referred to as “floaters” play critical roles in determining dynamics and stability of these populations. Floaters are difficult to study, however, so we lack data on the roles they play in population ecology and conservation status of many species. Here, we paired satellite telemetry and a new mechanistic space use model based on an Ornstein-Uhlenbeck process to study the differential habitat selection and space use of floater and territorial golden eagles Aquila chrysaetos. Our sample consisted of 49 individuals tracked over complete breeding seasons across four years, totalling 104 eagle breeding seasons. Modeling these data with the new mechanistic approach was required to parse key differences in movement and separate aspects of resource selection from central place behavior. We found that floaters generally had more expansive space use patterns and larger home ranges, partitioning space with territorial individuals seemingly on fine scales through differential habitat and resource selection. Floater and territorial eagle home ranges overlapped markedly, suggesting floaters use the interstices between territories. Further, floater and territorial eagles differed in how they selected for uplift variables, key components of soaring birds’ energy landscape, with territorial eagles apparently better able to find and use thermal uplift. We also found relatively low individual heterogeneity in resource selection, especially among territorial individuals, suggesting a narrow realized niche for breeding individuals. This work furthers our understanding of floaters’ potential roles in population ecology of territorial species, as well as suggests that conserving landscapes occupied by territorial eagles also protects floaters.

scholarly journals Family feud: permanent group splitting in a highly philopatric mammal, the killer whale (Orcinus orca)

2021 ◽  
Vol 75 (3) ◽  
Author(s):  
Eva H. Stredulinsky ◽  
Chris T. Darimont ◽  
Lance Barrett-Lennard ◽  
Graeme M. Ellis ◽  
John K. B. Ford
Keyword(s):  
Killer Whale ◽  
Group Structure ◽  
Group Living ◽  
Orcinus Orca ◽  
Learning Approaches ◽  
Killer Whales ◽  
Internal Factors ◽  
Individual Fitness ◽  
Leadership Experience

Abstract For animals that tend to remain with their natal group rather than individually disperse, group sizes may become too large to benefit individual fitness. In such cases, group splitting (or fission) allows philopatric animals to form more optimal group sizes without sacrificing all familiar social relationships. Although permanent group splitting is observed in many mammals, it occurs relatively infrequently. Here, we use combined generalized modeling and machine learning approaches to provide a comprehensive examination of group splitting in a population of killer whales (Orcinus orca) that occurred over three decades. Fission occurred both along and across maternal lines, where animals dispersed in parallel with their closest maternal kin. Group splitting was more common: (1) in larger natal groups, (2) when the common maternal ancestor was no longer alive, and (3) among groups with greater substructuring. The death of a matriarch did not appear to immediately trigger splitting. Our data suggest intragroup competition for food, leadership experience and kinship are important factors that influence group splitting in this population. Our approach provides a foundation for future studies to examine the dynamics and consequences of matrilineal fission in killer whales and other taxa. Significance statement Group living among mammals often involves long-term social affiliation, strengthened by kinship and cooperative behaviours. As such, changes in group membership may have significant consequences for individuals’ fitness and a population’s genetic structure. Permanent group splitting is a complex and relatively rare phenomenon that has yet to be examined in detail in killer whales. In the context of a growing population, in which offspring of both sexes remain with their mothers for life, we provide the first in-depth examination of group splitting in killer whales, where splitting occurs both along and across maternal lines. We also undertake the first comprehensive assessment of how killer whale intragroup cohesion is influenced by both external and internal factors, including group structure, population and group demography, and resource abundance.

scholarly journals Critical In-Water Habitats for Post-Nesting Sea Turtles from the Southern Gulf of Mexico

2021 ◽  
Vol 9 (8) ◽  
pp. 793
Author(s):  
Abigail Uribe-Martínez ◽  
María de los Angeles Liceaga-Correa ◽  
Eduardo Cuevas
Keyword(s):  
Gulf Of Mexico ◽  
Marine Ecosystem ◽  
Satellite Telemetry ◽  
Marine Turtle ◽  
Home Ranges ◽  
The Bahamas ◽  
Turtle Species ◽  
Southern Gulf Of Mexico ◽  
Large Marine Ecosystem ◽  
Physical Features

Marine turtles are globally endangered species that spend more than 95% of their life cycle in in-water habitats. Nevertheless, most of the conservation, recovery and research efforts have targeted the on-land habitats, due to their easier access, where adult females lay their eggs. Targeting the large knowledge gaps on the in-water critical habitats of turtles, particularly in the Large Marine Ecosystem Gulf of Mexico, is crucial for their conservation and recovery in the long term. We used satellite telemetry to track 85 nesting females from their beaches after they nested to identify their feeding and residency habitats, their migratory corridors and to describe the context for those areas. We delimited major migratory corridors in the southern Gulf of Mexico and West Caribbean and described physical features of internesting and feeding home ranges located mainly around the Yucatan Peninsula and Veracruz, Mexico. We also contributed by describing general aggregation and movement patterns for the four marine turtle species in the Atlantic, expanding the knowledge of the studied species. Several tracked individuals emigrated from the Gulf of Mexico to as far as Nicaragua, Honduras, and the Bahamas. This information is critical for identifying gaps in marine protection and for deciphering the spatial connectivity in large ocean basins, and it provides an opportunity to assess potential impacts on marine turtle populations and their habitats.

scholarly journals The home-range concept: are traditional estimators still relevant with modern telemetry technology?

2010 ◽  
Vol 365 (1550) ◽  
pp. 2221-2231 ◽  
Author(s):  
John G. Kie ◽  
Jason Matthiopoulos ◽  
John Fieberg ◽  
Roger A. Powell ◽  
Francesca Cagnacci ◽  
...  
Keyword(s):  
Home Range ◽  
New Technologies ◽  
Animal Movement ◽  
Space Use ◽  
Ease Of Use ◽  
Home Ranges ◽  
Data Intensive ◽  
Use Patterns ◽  
Location Data ◽  
Utilization Distributions

Recent advances in animal tracking and telemetry technology have allowed the collection of location data at an ever-increasing rate and accuracy, and these advances have been accompanied by the development of new methods of data analysis for portraying space use, home ranges and utilization distributions. New statistical approaches include data-intensive techniques such as kriging and nonlinear generalized regression models for habitat use. In addition, mechanistic home-range models, derived from models of animal movement behaviour, promise to offer new insights into how home ranges emerge as the result of specific patterns of movements by individuals in response to their environment. Traditional methods such as kernel density estimators are likely to remain popular because of their ease of use. Large datasets make it possible to apply these methods over relatively short periods of time such as weeks or months, and these estimates may be analysed using mixed effects models, offering another approach to studying temporal variation in space-use patterns. Although new technologies open new avenues in ecological research, our knowledge of why animals use space in the ways we observe will only advance by researchers using these new technologies and asking new and innovative questions about the empirical patterns they observe.

Development of intentional stranding hunting techniques in killer whale (Orcinus orca) calves at Crozet Archipelago

1995 ◽  
Vol 73 (1) ◽  
pp. 27-33 ◽  
Author(s):  
Christophe Guinet ◽  
Jérome Bouvier
Keyword(s):  
Growth Curve ◽  
Parental Investment ◽  
Killer Whale ◽  
Elephant Seal ◽  
Orcinus Orca ◽  
Killer Whales ◽  
Juvenile Female ◽  
Adult Females ◽  
Social Transfer ◽  
High Degree

This paper describes the trend in the practice of what we interpret to be the "intentional stranding" hunting technique of two juvenile female killer whales (Orcinus orca), A4 and A5, belonging to pod A on the beaches of Possession Island, Crozet Archipelago. Pod A was composed of three adult females, A2, A3, A6, and one adult male, A1. A2 is A4's mother and A3 is A5's mother. The year of birth and thus the probable age of the two juveniles were estimated from their growth curve determined by means of a photogrammetric technique. These observations indicate that at Crozet Archipelago, juvenile killer whales first practiced intentional stranding on their own when they were 4–5 years old. Their first attempt to capture elephant seal pups by means of this technique was observed when they were 5–6 years old. However, 5- to 6-year-old juveniles still needed the assistance of an adult female to return to the water with their prey. This study indicates that learning hunting techniques needs a high degree of skill and requires high parental investment to reduce the associated risk. Furthermore, social transfer, through apprenticeship, is probably one of the mechanisms that enables the high degree of adaptability observed in killer whales.

scholarly journals A long post-reproductive lifespan is a shared trait among genetically distinct killer whale populations

2021 ◽  
Author(s):  
Mia Nielsen ◽  
Samuel Ellis ◽  
Jared Towers ◽  
Thomas Doniol-Valcroze ◽  
Daniel Franks ◽  
...  
Keyword(s):  
Social Structure ◽  
Killer Whale ◽  
Demographic Data ◽  
Reproductive Period ◽  
Substantial Variation ◽  
Killer Whales ◽  
Reproductive Conflict ◽  
Demographic Patterns ◽  
General Prediction

The extended female post-reproductive lifespan found in humans and some toothed whales remains an evolutionary puzzle. Theory predicts demographic patterns resulting in increased female relatedness with age (kinship dynamics) can select for a prolonged post-reproductive lifespan due to the combined costs of inter-generational reproductive conflict and benefits of late-life helping. Here we test this prediction using >40 years of longitudinal demographic data from the sympatric yet genetically distinct killer whale ecotypes: resident and Bigg’s killer whales. The female relatedness with age is predicted to increase in both ecotypes, but with a less steep increase in Bigg’s due to their different social structure. Here, we show that there is a significant post-reproductive lifespan in both ecotypes with >30% of adult female years being lived as post-reproductive, supporting the general prediction that an increase in local relatedness with age predisposes the evolution of a post-reproductive lifespan. Differences in the magnitude of kinship dynamics however, did not influence the timing or duration of the post-reproductive lifespan with females in both ecotypes terminating reproduction before their mid-40s followed by an expected post-reproductive period of ~20 years. Our results highlight the important role of kinship dynamics in the evolution of a long post-reproductive lifespan in long-lived mammals, while further implying that the timing of menopause may be a robust trait that is persistent despite substantial variation in demographic patterns among population.

scholarly journals Mitigating killer whale depredation on demersal longline fisheries by changing fishing practices

2014 ◽  
Vol 72 (5) ◽  
pp. 1610-1620 ◽  
Author(s):  
Paul Tixier ◽  
Jade Vacquie Garcia ◽  
Nicolas Gasco ◽  
Guy Duhamel ◽  
Christophe Guinet
Keyword(s):  
Killer Whale ◽  
Collaborative Work ◽  
Dilution Effect ◽  
Killer Whales ◽  
Fleet Size ◽  
Operational Variables ◽  
Definition Of ◽  
Longline Fisheries ◽  
Technical Solutions ◽  
Fishing Practices

Abstract Odontocete depredation on longlines involves socioeconomic and conservation issues with significant losses for fisheries and potential impacts on wild populations of depredating species. As technical solutions to this conflict are limited and difficult to implement, this study aimed to identify fishing practices that could reduce odontocete depredation, with a focus on killer whales (Orcinus orca) interacting with Patagonian toothfish (Dissostichus eleginoides) longliners off the Crozet islands. Data collected by fishery observers from 6013 longline sets between 2003 and 2013 allowed us to statistically detect the significant influence of five operational variables using GLMMs. The probability of interactions between vessels and killer whales was decreased by (i) the number of vessels operating simultaneously in the area: the limited number of depredating killer whales may induce a dilution effect with increased fleet size, and (ii) depth of longline sets: vessels operating in shallow waters may be more accessible to whales that are initially distributed on peri-insular shelves. The cpue was negatively influenced by (iii) length of longlines: longer sets may provide killer whales access to a greater proportion of hooked fish per set, and positively influenced by (iv) hauling speed: increased speed may shorten the time during which toothfish are accessible to whales during hauling. The time it takes for killer whales to reach vessels was positively correlated to (v) the distance travelled between longline sets with an estimated threshold of 100 km beyond which whales seem to temporarily lose track of vessels. These findings provide insightful guidelines about what fishing strategy to adopt given these variables to reduce killer whale depredation here and in similar situations elsewhere. To a greater extent, this study is illustrative of how collaborative work with fishermen in a fully controlled fishery framework may lead to the definition of cost-limited and easy-to-implement mitigation solutions when facing such human-wildlife conflict.

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