Estimated abundances of cetacean species in the Northeast Atlantic from Norwegian shipboard surveys conducted in 2014-2018

A ship-based mosaic survey of Northeast Atlantic cetaceans was conducted over a 5-year period between 2014–2018. The area surveyed extends from the North Sea in the south (southern boundary at 53oN), to the ice edge of the Barents Sea and the Greenland Sea. Survey vessels were equipped with 2 independent observer platforms that detected whales in passing mode and applied tracking procedures for the target species, common minke whales (Balaenoptera acutorostrata acutorostrata). Here we present abundance estimates for all non-target species for which there were sufficient sightings. We estimate the abundance of fin whales (Balaenoptera physalus) to be 11,387 (CV=0.17, 95% CI: 8,072–16,063), of humpback whales (Megaptera novaeangliae) to be 10,708 (CV=0.38, 95% CI: 4,906–23,370), of sperm whales (Physeter macrocephalus) to be 5,704 (CV=0.26, 95% CI: 3,374–9,643), of killer whales (Orcinus orca) to be 15,056 (CV=0.29, 95% CI: 8,423–26,914), of harbour porpoises (Phocoena phocoena) to be 255,929 (CV=0.20, 95% CI: 172,742–379,175), dolphins of genus Lagenorhynchus to be 192,767 (CV=0.25, 95% CI: 114,033–325,863), and finally of northern bottlenose whales (Hyperoodon ampullatus) to be 7,800 (CV=0.28, 95% CI: 4,373–13,913). Additionally, our survey effort in the Norwegian Sea in 2015 contributed to the 6th North Atlantic Sightings Survey (NASS) and the survey was extended into the waters north and east of Iceland around Jan Mayen island. This NASS extension, along with our Norwegian Sea survey in 2015, was used to estimate the abundance of fin whales, humpback whales, and sperm whales. All estimates presented used mark-recapture distance sampling techniques and were thus corrected for perception bias. Our estimates do not account for additional variance due to distributional shifts between years or biases due to availability or responsive movement.publishedVersio

Estimated abundances of cetacean species in the Northeast Atlantic from two multiyear surveys conducted by Norwegian vessels between 2002-2013

Two shipboard line-transect surveys of the Northeast Atlantic were conducted between 2002–2007 and 2008–2013 to meet the ongoing requirements of the Revised Management Procedure (RMP) for common minke whales (Balaenoptera acutorostrata acutorostrata) developed by the International Whaling Commission’s Scientific Committee. Here we present estimated abundances for non-target species for which there were sufficient sightings, including fin whales (Balaenoptera physalus), humpback whales (Megaptera novaeangliae), sperm whales (Physeter macrocephalus), killer whales (Orcinus orca), harbour porpoises (Phocoena phocoena), and dolphins of genus Lagenorhynchus. The 2 surveys were conducted using a multiyear mosaic survey design with 2 independent observer platforms operating in passing mode, each with 2 observers. The abundances of Lagenorhynchus spp. from the 2002–2007 survey were estimated using single-platform standard distance sampling methods because of uncertainty in identifying duplicate sightings. All other estimates were derived using mark-recapture distance sampling techniques applied to a combined-platform dataset of observations, correcting for perception bias. Most notably, we find that the abundance of humpback whales, similar in both survey periods, has doubled since the 1990s with the most striking changes occurring in the Barents Sea. We also show that the pattern in distribution and abundance of fin whales and sperm whales is consistent with our earlier surveys, and that abundances of small odontocete species, which were not estimated in earlier surveys, show stable distributions with some variation in their estimates. Our estimates do not account for distributional shifts between years or correct for biases due to availability or responsive movement.publishedVersio

A fluke encounter: first record of the blue whale (Balaenoptera musculus) within the central North Sea, United Kingdom

Despite holding the accolade as the largest animal ever to live on planet earth and ubiquitously inhabiting the world's major oceans, an acute paucity of information surrounds the geographical distribution and migration phenology of the endangered blue whale (Balaenoptera musculus) in the northeast Atlantic. Current migration and distribution information derived from robust scientific studies is required to ensure the formulation and implementation of successful conservation measures with a vision to support the ongoing recovery of the northeast Atlantic population. At 10:21 (UTC) on the 9th of November 2020, two blue whales were observed at position 55°13.99′N, 01°13.62′W, 18 km off the coast of the UK in the central North Sea just north of Newcastle at a water depth of 76 m. This is the first paper that has confirmed an account of live blue whales frequenting shallow waters of the central North Sea and represents a new area of occurrence within the accepted range of the northeast Atlantic population, an area in which sightings are extremely rare and may provide insight into the intricacies of migration routes and behaviour.publishedVersio

Consideration of measurement errors for the Norwegian common minke whale (Balaenoptera acutorostrata acutorostrata) surveys

A discrete measurement error model for radial distance and angle to detected objects in line transect surveys is considered. This approach directly quantifies the effect of measurement error on the estimated effective strip half-width. We apply the method to experimental data collected over the period 2008-2013 in North Atlantic both under the assumption of multiplicative and additive measurement errors. Our results indicate that the abundance estimates considering the measurement error are consistently larger than the abundance estimates without any measurement error correction.publishedVersio

Autumn movements of fin whales (Balaenoptera physalus) from Svalbard, Norway, revealed by satellite tracking

Insight into animal movements is essential for understanding habitat use by individuals as well as population processes and species life-history strategies. In this study, we instrumented 25 fin whales with ARGOS satellite-transmitters in Svalbard, Norway, to study their movement patterns and behaviour (Area Restricted Search (ARS), transiting or unknown) during boreal autumn/early winter. Ten of the whales stayed in the tagging area (most northerly location: 81.68°N) for their entire tracking periods (max 45 days). The other 15 whales moved in a south-westerly direction; the longest track ended off the coast of northern Africa (> 5000 km from the tagging location) after 96 days. The whales engaged in ARS behaviour intermittently throughout their southward migrations. During transit phases the whales moved quickly; one individual maintained an average horizontal speed of 9.3 km/h (travelling 223 km per day) for a period of a week. This study documents that: (1) some fin whales might remain at high latitudes during winter; (2) the whales that do migrate probably feed along the way; (3) they can maintain high transiting speed for long periods and; (4) one breeding area for this species is likely located in deep, warm water some 100 km west of Morocco.publishedVersio

Forskerutvalg om sjøpattedyr 2021 - Råd om forskning og forvaltning

Forskerutvalg om sjøpattedyr som ble opprettet i 2009, består av femten forskere fra syv forskningsinstituttet i Norge. Utvalget møttes 21.-22. oktober i Tromsø for å utarbeide anbefalinger om forvaltning, vern og forskning på sjøpattedyr i 2022. Det foreligger et nytt bestandsestimat for vågehval basert på tellinger i 2014-2019. Dette estimatet som er ca 50% høyere enn i tidligere telleperioder, skal behandles av IWC’s Vitenskapskomité våren 2022 og legges til grun for et nytt Implementation Review. Anbefaling om kvoter for 2022 må utarbeides før IWC’s behandling foreligger. HI må derfor gjøre simuleringene selv som grunnlag for kvoteråd. For grønlandssel i Vesterisen ga Utvalget sin tilslutning til anbefalingene fra ICES om en kvote på 11 548 dyr i 2021. Utvalget gir også sin tilslutning til anbefalingen fra ICES om en kvote på 21 172 grønlandssel i Østisen for 2021. (Den Blandede Norsk-Russiske Fiskerikommisjonen allokerte i et virtuelt møte den 12.-16. oktober 2020,publishedVersio

Forskerutvalg om sjøpattedyr 2019 - Anbefalinger om forskning og forvaltning

Forskerutvalg om sjøpattedyr som ble opprettet i 2009, består av femten forskere fra syv forskningsinstitutter i Norge. Utvalget møttes 24.-25. oktober 2019 i Tromsø for å utarbeide anbefalinger om forvaltning, vern og forskning på sjøpattedyr i 2020. Utvalget anbefalte at ‘Potential Biological Removal’ (PBR) burde legges til grunn for å beregne høstingskvoten for grønlandssel ved Jan Mayen (Vesterisen) og den anbefalte kvoten ble dermed 11 548 sel i 2020. Dette er i samsvar med råd fra ICES. Utvalget anbefalte å opprettholde full fredning av klappmyss ved Jan Mayen, dog slik at et mindre antall dyr kan tas til vitenskapelige formål. For grønlandssel i Barentshavet (Østisen) anbefalte Utvalget at kvoten skulle baseres på PBR med en konservativ ‘Recovery factor’ på 0,25. Den anbefalte kvoten for 2020 blir da 21 172 sel. Dette er i samsvar med råd fra ICES. For havert og steinkobbe på norskekysten anbefalte Utvalget jaktkvoter på henholdsvis 200 og 467 sel. Full fredning av havert mellom Stad og Lofoten og fredning av små, isolerte bestander av steinkobbe ble anbefalt opprettholdt. For høsting av vågehval anbefalte Utvalget at kvoten fortsatt bør baseres på ‘Revised Management Procedure’ som ble utviklet for forvaltning av bardehval av Vitenskapskomiteen til Den internasjonale hvalfangstkommisjonen (IWC). Alle andre hvalarter forblir fredet i Norge. Utvalget anbefalte videre obligatorisk bruk av akustiske alarmer på noen garnfiskerier og områder for å avbøte høye bifangster av nise. Endelig vedtok Utvalget en rekke anbefalinger om videre forskning for å styrke kunnskapsgrunnlaget for forvaltning, vern og dyrevelferd av sjøpattedyr i Norge og for å øke forståelsen av sjøpattedyrenes roller i økosystemene.publishedVersio

Forskerutvalg om sjøpattedyr 2020 - Tilrådning om forskning og forvaltning

Forskerutvalg om sjøpattedyr som ble opprettet i 2009, består av femten forskere fra syv forskningsinstituttet i Norge. Utvalget møttes 22.-23. oktober i Tromsø for å utarbeide anbefalinger om forvaltning, vern og forskning på sjøpattedyr i 2021.publishedVersio

Toktrapport fra det norsk/russiske økotoktet i Barentshavet og nærliggende områder

The aim of the joint Norwegian/Russian ecosystem survey in the Barents Sea and adjacent waters, August-October (BESS) is to monitor the status and changes in the Barents Sea ecosystem and provide data to support stock advice and research. The survey has since 2004 been conducted annually in the autumn, as a collaboration between the Institute of Marine Research (IMR) in Norway and the Polar branch of the VNIRO (PINRO) in Russia. The general survey plan and tasks were agreed upon at the annual IMR-PINRO Meeting in March 2022. Ship routes and other technical details are agreed on by correspondence between the survey coordinators. BESS aims at covering the entire Barents Sea. Ecosystem stations are distributed in a 35×35 nautical mile regular grid, and the ship tracks follow this design. Exceptions are the area around Svalbard (Spitsbergen), some additional bottom trawl hauls for demersal fish survey indices estimation, and additional acoustic transects for the capelin stock size estimation. Survey start for the Russian vessel was significantly delayed, resulting in REEZ being covered two-three months later than NEEZ. This resulted in reduced area coverage, decrease in the numbers of trawl hauls, and lack of standard pelagic trawl sampling. In NEEZ, RV “Kronprins Haakon” was cancelled due to difficult economic situation, making it necessary to allocate one of the two remaining vessels to the area west and north of Svalbard (Spitsbergen). This resulted in low coverage in this area, and problems with synoptic coverage in north-east of Svalbard (Spitsbergen) and thus increased uncertainty in assessment of demersal fish (e.g. Greenland halibut) and capelin. The 19-th joint Barents Sea autumn Ecosystem Survey (BESS) was carried out in two periods. The Norwegian research vessels “G.O. Sars” and “Johan Hjort” covered NEEZ in the period 16-th August to 03-th October, providing data to stock assessment, 0-group fish abundance indices, and state and changes descriptions which is comparable with earlier survey years in NEEZ. The Russian research vessel “Vilnyus” covered REEZ in the periods 20-th to 30-th September and 22-th October to 3-rd December. Survey coordinators in 2022 were Dmitry Prozorkevich (PINRO) and Geir Odd Johansen (IMR). Exchange of Russian and Norwegian experts between each country’s respective vessels did not take place in 2022. We would like to express our sincere gratitude to all the crew and scientific personnel onboard RVs “Vilnyus”, “G.O. Sars” and “Johan Hjort” for their dedicated work, as well as all the people involved in planning and reporting of BESS 2022. This report is a summary of observations and status assessment based on the survey data. Even though the survey was not well completed, the data obtained are the main source of knowledge about the ecosystem of the Barents Sea.Survey report from the joint Norwegian/Russian Ecosystem Survey in the Barents Sea and the adjacent waters August- December 2022publishedVersio

Panel-based Assessment of Ecosystem Condition of Norwegian Barents Sea Shelf Ecosystems - Appendices

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