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Friday Harbor, WA, United States

News Article
Site: http://phys.org/biology-news/

Researchers follow them by drone and by sea, analyzing their waste and their exhaled breath. Now, experts want to add another layer to the exhaustive studies: individual health records for each endangered whale. The records would take existing research on the creatures and combine it in one place. The idea is to use them to monitor the orcas' health trends individually and as a population. It's similar to people having one medical record as they move from one doctor to the next or between specialists. Eighty-four orcas typically appear in Puget Sound from spring to fall. "The goal is to really start getting a lot of data and pull them together in a way that permits easier analysis," said Joe Gaydos, a wildlife veterinarian at the University of California, Davis, and chief scientist with the SeaDoc Society, which is part of the university's School of Veterinary Medicine. "Ultimately, the real benefit of any health record is to help make (management) decisions," he added. For example, if an orca appears emaciated or is in bad shape during certain times of the year, wildlife managers can access the animal's health history to see what's going on and what they could do about it, he said. Understanding the factors that affect an orca's health will ultimately help pinpoint the key threats and how to reduce them, experts say. "It will be really powerful to rule out things that aren't important and focus in on what's really important," said Lynne Barre with NOAA Fisheries. She said that will help inform research and management decisions in the long run. The project aims to pull together data on behavior, reproductive success, skin diseases and other study areas to allow for integrated analysis, she said. Scientists have enough data that they can now connect the dots to get meaningful answers, said Brad Hanson, an NOAA Fisheries wildlife biologist. More than two dozen wildlife experts met in Seattle on Tuesday to develop plans for health records for the orcas. The meeting was sponsored by SeaDoc Society, the National Oceanic and Atmospheric Administration Fisheries and the National Marine Mammal Foundation. Many details are still being worked out, including who will maintain the data and how people will access it. But an initial database would be launched this summer using readily available information, such as sex, age, gender and other details, Gaydos said. Other information would be added next year. Elsewhere, scientists have studied individual animals to monitor their health, including North Atlantic right whales. Using a database of hundreds of thousands of photographs taken over decades, researchers at the New England Aquarium and others have studied the body and skin conditions of about 400 individual right whales to assess their health. Individual Puget Sound orcas are identified by unique black and white markings or variations in their fin shapes, and each whale is given a number and a name. The Center for Whale Research on San Juan Island keeps the federal government's annual census on the population. The three families—the J, K, and L pods—are genetically and behaviorally distinct from other killer whales. They use unique calls to communicate with one another and eat salmon rather than marine mammals. Their numbers have fluctuated in recent decades as they have faced threats from pollution, lack of prey and disturbance from boats. They were listed as endangered in 2005.


News Article
Site: http://www.biosciencetechnology.com/rss-feeds/all/rss.xml/all

The killer whales that spend time in the inland waters of Washington state already are tagged and tracked, photographed and measured. Researchers follow them by drone and by sea, analyzing their waste and their exhaled breath. Now, experts want to add another layer to the exhaustive studies: individual health records for each endangered whale. The records would take existing research on the creatures and combine it in one place. The idea is to use them to monitor the orcas' health trends individually and as a population. It's similar to people having one medical record as they move from one doctor to the next or between specialists. Eighty-four orcas typically appear in Puget Sound from spring to fall. "The goal is to really start getting a lot of data and pull them together in a way that permits easier analysis," said Joe Gaydos, a wildlife veterinarian at the University of California, Davis, and chief scientist with the SeaDoc Society, which is part of the university's School of Veterinary Medicine. "Ultimately, the real benefit of any health record is to help make (management) decisions," he added. For example, if an orca appears emaciated or is in bad shape during certain times of the year, wildlife managers can access the animal's health history to see what's going on and what they could do about it, he said. Understanding the factors that affect an orca's health will ultimately help pinpoint the key threats and how to reduce them, experts say. "It will be really powerful to rule out things that aren't important and focus in on what's really important," said Lynne Barre with NOAA Fisheries. She said that will help inform research and management decisions in the long run. The project aims to pull together data on behavior, reproductive success, skin diseases and other study areas to allow for integrated analysis, she said. Scientists have enough data that they can now connect the dots to get meaningful answers, said Brad Hanson, an NOAA Fisheries wildlife biologist. More than two dozen wildlife experts met in Seattle on Tuesday to develop plans for health records for the orcas. The meeting was sponsored by SeaDoc Society, the National Oceanic and Atmospheric Administration Fisheries and the National Marine Mammal Foundation. Many details are still being worked out, including who will maintain the data and how people will access it. But an initial database would be launched this summer using readily available information, such as sex, age, gender and other details, Gaydos said. Other information would be added next year. Elsewhere, scientists have studied individual animals to monitor their health, including North Atlantic right whales. Using a database of hundreds of thousands of photographs taken over decades, researchers at the New England Aquarium and others have studied the body and skin conditions of about 400 individual right whales to assess their health. Individual Puget Sound orcas are identified by unique black and white markings or variations in their fin shapes, and each whale is given a number and a name. The Center for Whale Research on San Juan Island keeps the federal government's annual census on the population. The three families - the J, K, and L pods - are genetically and behaviorally distinct from other killer whales. They use unique calls to communicate with one another and eat salmon rather than marine mammals. Their numbers have fluctuated in recent decades as they have faced threats from pollution, lack of prey and disturbance from boats. They were listed as endangered in 2005.


Ford J.K.B.,Canadian Department of Fisheries and Oceans | Ellis G.M.,Canadian Department of Fisheries and Oceans | Olesiuk P.F.,Canadian Department of Fisheries and Oceans | Balcomb K.C.,Center for Whale Research
Biology Letters | Year: 2010

Killer whales (Orcinus orca) are large predators that occupy the top trophic position in the world's oceans and as such may have important roles in marine ecosystem dynamics. Although the possible top-down effects of killer whale predation on populations of their prey have received much recent attention, little is known of how the abundance of these predators may be limited by bottom-up processes. Here we show, using 25 years of demographic data from two populations of fish-eating killer whales in the northeastern Pacific Ocean, that population trends are driven largely by changes in survival, and that survival rates are strongly correlated with the availability of their principal prey species, Chinook salmon (Oncorhynchus tshawytscha). Our results suggest that, although these killer whales may consume a variety of fish species, they are highly specialized and dependent on this single salmonid species to an extent that it is a limiting factor in their population dynamics. Other ecologically specialized killer whale populations may be similarly constrained to a narrow range of prey species by culturally inherited foraging strategies, and thus are limited in their ability to adapt rapidly to changing prey availability. © 2009 The Royal Society. Source


Braithwaite J.E.,University of Western Australia | Meeuwig J.J.,University of Western Australia | Jenner K.C.S.,Center for Whale Research
PLoS ONE | Year: 2012

Conservation of large ocean wildlife requires an understanding of how they use space. In Western Australia, the humpback whale (Megaptera novaeangliae) population is growing at a minimum rate of 10% per year. An important consideration for conservation based management in space-limited environments, such as coastal resting areas, is the potential expansion in area use by humpback whales if the carrying capacity of existing areas is exceeded. Here we determined the theoretical carrying capacity of a known humpback resting area based on the spacing behaviour of pods, where a resting area is defined as a sheltered embayment along the coast. Two separate approaches were taken to estimate this distance. The first used the median nearest neighbour distance between pods in relatively dense areas, giving a spacing distance of 2.16 km (±0.94). The second estimated the spacing distance as the radius at which 50% of the population included no other pods, and was calculated as 1.93 km (range: 1.62-2.50 km). Using these values, the maximum number of pods able to fit into the resting area was 698 and 872 pods, respectively. Given an average observed pod size of 1.7 whales, this equates to a carrying capacity estimate of between 1187 and 1482 whales at any given point in time. This study demonstrates that whale pods do maintain a distance from each other, which may determine the number of animals that can occupy aggregation areas where space is limited. This requirement for space has implications when considering boundaries for protected areas or competition for space with the fishing and resources sectors. © 2012 Braithwaite et al. Source


Makelainen P.H.,University of Helsinki | Van Ginneken A.M.,Center for Whale Research | Pietiainen H.,University of Helsinki
Annales Zoologici Fennici | Year: 2013

The killer whale (Orcinus orca) is a top predator and one of the most contaminated marine mammal species in the world. Due to different prey preferences and life styles, killer whale populations accumulate persistent pollutants differently, and therefore are exposed differently to this stress. Stress may express itself in a population as an increase in the relative number of individuals with asymmetric presentation of a trait that is normally symmetrical. This phenomenon is called fluctuating asymmetry. There are many environmental and genetic factors that can cause fluctuating asymmetry. We have used the symmetry of the killer whale's saddle patch pattern behind the dorsal fin as an indicator of fluctuating asymmetry in six Pacific Ocean populations. The southern resident killer whale population seems to be remarkably more asymmetrical than the other studied populations. Although many possible environmental factors could cause asymmetry, we suggest that small population size, development of reproductively isolated ecotypes and possible inbreeding as genetic factors are causing asymmetry in the southern resident population. © Finnish Zoological and Botanical Publishing Board 2013. Source

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