KILLER WHALE RESEARCH
In wildlife management, scientific data and literature are necessary to inform status assessments and to further design effective conservation strategies. In this regard, Norwegian Orca Survey aims at publishing the most up-to-date knowledge on the killer whales that frequent the Norwegian Sea. To achieve this goal, we have been in the field researching Norwegian killer whales in all seasons since 2013.
In collaboration with Norwegian and international partners, we are working on multiple research projects that focus on population dynamics, movement patterns, diet, behavioral ecology, ecotoxicology, health status, social structure and genetics. Objectives are achieved using the below research methods and ongoing projects.
Individual recognition, through photo-identification, is the absolute foundation of all our studies. Using the shape of the dorsal fin, along with the pigmentation and scaring patterns of the adjacent grey 'saddle patch', individuals can be reliably identified and catalogued. An extensive catalogue and database (registry) have been built over the years and compiles sighting histories of the identified whales - in other words, we keep a log of who was seen, where, when and with whom. Additional data on individuals have been collected over the years (see below), which allowed us to build unprecedented knoweldge of Norwegian killer whale individual and groups.
Using a remote darting system, we collect skin and blubber samples of identified killer whales. In the lab, tissue samples are used for a series of analyses. For example, dietary markers are used to identify feeding preferences and foraging areas while contaminant loads are measured in the blubber layer to assess killer whales' health status. Genetic analyses are also conducted to study the patterns of relatedness among individuals and the genetic population structure. Biopsy sampling has been used routinely in marine mammal research around the world and does not induce any long lasting disturbance or injury. Sampling is conducted in compliance with Norwegian animal ethics and under permit from the Norwegian authorities.
Tags and Drones
To investigate killer whale behaviours, we attach data loggers with inbuilt cameras using suction cups. During the few hours (and up to a couple of days) of attachment, the multiple sensors continuously log motion data that are then used to study dive characteristics, behaviour, prey captures and interactions with other whales. We were the very first research team to deploy camera-tags on killer whales in Norway. Some of the resulting animal-borne video footage was featured in the first episode of Blue Planet II. Flying drones above whales enables us to further collect observations of subsurface behaviours and social dynamics. Aerial still photographs are also useful to assess killer whales' body condition, indicative of general health status.
The ongoing project MULTIWHALE is a collaboration between Norwegian Orca Survey, the University of Oslo, the Institute of Marine Research, the Norwegian University of Life Sciences (NMBU, Oslo) and the Norwegian University of Science and Technology (NTNU, Trondheim). International partners include researchers from McGill University, the University of Saint Andrews, Fisheries and Oceans Canada, and Ocean Wise Conservation Association. The project was funded by the Research Council of Norway and studies the complex question of how multiple stressors (anthropogenic pollutants, disturbance from whale watching activities, and nutritional status) may affect biological responses such as gene expression, endocrine, physiological, and behaviour at the individual and population levels in Norwegian killer whales.
We consider this in the context of intra-population variations in feeding ecology; some individuals are fish-specialists while others eat marine mammals in addition to fish. The latter are exposed to higher levels of pollutants, and thus may be more susceptible to the effects of anthropogenic stressors. We combine field studies, laboratory measurements and modelling tools to understand the short-term individual and long-term population level effects of multiple stressors, and how the effects are distributed within this ecologically structured population.
Risk assessments for marine mammals are often made in relation to a single stressor (e.g. pollution). However, the effects of individual stressors can be potentiated when occurring together. For example, lipid soluble contaminants are stored in the blubber, but can be remobilised in times of nutritional stress and start circulating in the blood and target organs. Similarly, acute stress from e.g. vessel disturbance can alter the ability to conserve metabolic stores by inducing gene networks that promote lipolysis and adipogenesis in mammalian adipocytes. Both nutritional stress and high levels of contaminants can negatively impact individuals' survival and reproduction, with further consequences on abundance and population growth.
MULTIWHALE will lead to important results that will improve our understanding of how a long-lived, social and wide-ranging top predator may respond to cumulative effects of multiple stressors. Presently facing a rapidly changing world, and with ecosystems being increasingly impacted by human stressors, the MULTIWHALE results will contribute to the growing and much needed field of multiple stressor ecology. Results will also have important implications for international contaminant regulations and implementation of sustainable tourism (whale watching). Lastly, our findings will be relevant to the assessment of population status of killer whales in Norway.
Read more here.
While our team has been mainly operating in northern Norway (Vesterålen and Troms), help from the general public also made possible to catalogue killer whales that inhabit the southern Norwegian fjords. Many people contributed photographs from their killer whale sightings over the past years. When quality of the photos allowed, the specific individuals were photo-identified and new records (of where and when seen) were added to the database. This approach, called ‘citizen-science’, enabled building an ID-Catalogue and understanding of these killer whale groups. To improve the research effort focusing on these whales for the years to come, we designed NOS-Vestlandet, which aims at reinforcing our citizen-science approach and implement seasonal fieldwork with the help of local actors.
THE STRANDING PROGRAM
The stranding program aims at collecting tissue samples of dead stranded marine mammals, including cetaceans and seals, along the Norwegian coast. This ongoing program has been the very first and only systematic sampling effort in Norway so far.
A recent project (2018-2021), funded by Klima-og miljødepartementet (Arktisk 2030), aimed at measuring chemical pollution in stranded Norwegian whales. Chemical pollution (including persistent organic pollutants, POPs) may cause adverse health effects in whales, including immunosuppression and reproductive impairment. POP-induced reproductive toxicity is the leading hypothesis for the declining whale and dolphin populations in European waters. However, research on levels and effects of marine pollution in whales in Norway has been scarce to date. Obtaining tissues from dead cetaceans offers the possibility to quantify contaminant concentrations. In addition, doing a full screening of these animals allows for identification of emerging contaminants such as unregulated pesticides, new brominated flame retardants, perfluorinated substances and chlorinated paraffins. As part of this project, Norwegian Orca Survey coordinated sample collection from 10 different species all over Norway, marking the very first systematic effort put into sampling stranded cetaceans in Norway. Members of the general public were of immense help, as many people assisted with sampling in remote locations. This project was a collaboration with the University of Oslo and the Norwegian University of Life Sciences. Results are underway and will be published soon. Findings will provide novel baseline knowledge available to the working groups of the Arctic Council and to be used for further international contaminant regulation work of REACH and the Stockholm Convention.
Our efforts in sampling dead stranded marine mammals in Norway continue, though is resource-dependent. If you find a dead whale or seal, please get in touch with us so we can organize necropsy or minimum sampling.
You can also check our already published results on stranded killer whales sampled in 2015-2017.
We recognise the greater value of focusing conservation efforts on populations rather than individuals. Nevertheless, we believe that animal welfare should be promoted whenever possible. Challenging situations involving single or small groups of cetaceans in distress may infrequently arise in coastal waters. These include by-catch or entanglement in fishing gears, live standings, natural entrapments in shallow bays, or sick or isolated individuals. Often, there are no protocols in place to manage these risky situations and outcomes appear rather uncertain. This may lead to important controversy and lack of action taken. To assist local communities and help with animal welfare, we travel onsite, conduct situation assessments and advise on possible solutions whenever possible. We always establish contact and solicit approvals from the Norwegian authorities prior initiating any intervention.
In May 2017, we initiated and led the rescue operation of five killer whales that entrapped in the small bay of Trælvikosen, Brønnøysund. Possibly, the long narrow and shallow inlet may have deterred the whales from returning to the open water. Because no fish schools could be detected in the bay and because the whales displayed signs of stress and malnutrition, a rescue operation involving the local community was conducted to free the whales. It took 25 boats and four hours to successfully drive the whales out. We assisted the Norwegian Directorate of Fisheries in a similar rescue of two entrapped killer whales on Vannøya, Troms in November 2019. These cases led to conducting a review of other natural killer whale entrapments recorded in other parts of the world. The resulting publication provides guidance on how to reliably identify entrapment situations and on intervention methods.
Perhaps the most unique case we had to deal with so far was the rescue of Hvaldimir, the beluga whale better known as the 'Russian spy-whale'. Apparently from a managed-care situation and possibly from a Russian facility, the friendly beluga whale was first spotted in Norwegian waters in April 2019. After two weeks spent in the industrial harbour of Hammerfest, Hvaldimir showed obvious signs of poor condition. To promote his welfare and survival while potential long-term solutions were reviewed and to be decided by the Norwegian authorities, we took charge of his feeding and monitoring program, under official permission. The delicate mission turned out to be successful as Hvaldimir apparently gained weight and became more energetic and active. 24/7 monitoring of his behaviour soon revealed a growing interest for live fish and prey capture attempts. Hvaldimir left Hammerfest in July 2019, and has been swimming on his own, feeding himself, ever since.