TY - JOUR
T1 - Estimating the abundance of the critically endangered Baltic Proper harbour porpoise (Phocoena phocoena) population using passive acoustic monitoring
AU - Amundin, Mats
AU - Carlström, Julia
AU - Thomas, Len
AU - Carlén, Ida
AU - Teilmann, Jonas
AU - Tougaard, Jakob
AU - Loisa, Olli
AU - Kyhn, Line A.
AU - Sveegaard, Signe
AU - Burt, M. Louise
AU - Pawliczka, Iwona
AU - Koza, Radomil
AU - Arciszewski, Bartlomiej
AU - Galatius, Anders
AU - Laaksonlaita, Jussi
AU - MacAuley, Jamie
AU - Wright, Andrew J.
AU - Gallus, Anja
AU - Dähne, Michael
AU - Acevedo-Gutiérrez, Alejandro
AU - Benke, Harald
AU - Koblitz, Jens
AU - Tregenza, Nick
AU - Wennerberg, Daniel
AU - Brundiers, Katharina
AU - Kosecka, Monika
AU - Tiberi Ljungqvist, Cinthia
AU - Jussi, Ivar
AU - Jabbusch, Martin
AU - Lyytinen, Sami
AU - Šaškov, Aleksej
AU - Blankett, Penina
N1 - The SAMBAH project was funded by the LIFE+ program of the European Commission (LIFE08 NAT/S/000261) and co-funded by Bundesamt für Naturschutz, Germany (SAMBAH II 5 Vw/52602/2011-Mar 36032/66); Bundesministerium für Umwelt, Naturschutz und Reaktorsicherheit, Germany (COSAMM FKZ 0325238); Carlsbergfondet, Denmark (CF16-0861); European Association of Zoos and Aquaria, The Netherlands; Główny Inpektorat Ochrony Środowiska, Poland; Havs-och Vattenmyndigheten, Sweden; Instytut Meteorologii i Gospodarki Wodnej - Państwowy Instytut Badawczy, Poland; Japanese Science and Technology Agency-CREST, Japan (7620-7); Kolmårdens Djurpark, Sweden; Maailman Luonnon Säätiö (WWF) Suomen Rahasto, Finland; Miljøministeriet, Denmark; Miljø- og Fødevareministeriet, Denmark (SN 343/SN-0008); Narodowy Fundusz Ochrony Środowiska i Gospodarki Wodnej, Poland (561/2009/Wn-50/OP/RE-LF/D); Naturvårdsverket, Sweden; SNAK Ph.D. School, Aarhus University, Denmark (91147/365); Tampereen Särkänniemi Ltd., Finland; Turun ammattikorkeakoulu Oy, Finland; Uniwersytet Gdański, Poland; Wojewódzki Fundusz Ochrony Środowiska i Gospodarki Wodnej w Gdańsku, Poland; and Ympäristöministeriö, Finland.
PY - 2022/2
Y1 - 2022/2
N2 - Knowing the abundance of a population is a crucial component to assess its conservation status and develop effective conservation plans. For most cetaceans, abundance estimation is difficult given their cryptic and mobile nature, especially when the population is small and has a transnational distribution. In the Baltic Sea, the number of harbour porpoises (Phocoena phocoena) has collapsed since the mid-20th century and the Baltic Proper harbour porpoise is listed as Critically Endangered by the IUCN and HELCOM; however, its abundance remains unknown. Here, one of the largest ever passive acoustic monitoring studies was carried out by eight Baltic Sea nations to estimate the abundance of the Baltic Proper harbour porpoise for the first time. By logging porpoise echolocation signals at 298 stations during May 2011-April 2013, calibrating the loggers' spatial detection performance at sea, and measuring the click rate of tagged individuals, we estimated an abundance of 71-1105 individuals (95% CI, point estimate 491) during May-October within the population's proposed management border. The small abundance estimate strongly supports that the Baltic Proper harbour porpoise is facing an extremely high risk of extinction, and highlights the need for immediate and efficient conservation actions through international cooperation. It also provides a starting point in monitoring the trend of the population abundance to evaluate the effectiveness of management measures and determine its interactions with the larger neighboring Belt Sea population. Further, we offer evidence that design-based passive acoustic monitoring can generate reliable estimates of the abundance of rare and cryptic animal populations across large spatial scales.
AB - Knowing the abundance of a population is a crucial component to assess its conservation status and develop effective conservation plans. For most cetaceans, abundance estimation is difficult given their cryptic and mobile nature, especially when the population is small and has a transnational distribution. In the Baltic Sea, the number of harbour porpoises (Phocoena phocoena) has collapsed since the mid-20th century and the Baltic Proper harbour porpoise is listed as Critically Endangered by the IUCN and HELCOM; however, its abundance remains unknown. Here, one of the largest ever passive acoustic monitoring studies was carried out by eight Baltic Sea nations to estimate the abundance of the Baltic Proper harbour porpoise for the first time. By logging porpoise echolocation signals at 298 stations during May 2011-April 2013, calibrating the loggers' spatial detection performance at sea, and measuring the click rate of tagged individuals, we estimated an abundance of 71-1105 individuals (95% CI, point estimate 491) during May-October within the population's proposed management border. The small abundance estimate strongly supports that the Baltic Proper harbour porpoise is facing an extremely high risk of extinction, and highlights the need for immediate and efficient conservation actions through international cooperation. It also provides a starting point in monitoring the trend of the population abundance to evaluate the effectiveness of management measures and determine its interactions with the larger neighboring Belt Sea population. Further, we offer evidence that design-based passive acoustic monitoring can generate reliable estimates of the abundance of rare and cryptic animal populations across large spatial scales.
KW - Abundance estimation
KW - C-POD
KW - Detection function
KW - Passive acoustic monitoring
KW - Phocoena phocoena
U2 - 10.1002/ece3.8554
DO - 10.1002/ece3.8554
M3 - Article
SN - 2045-7758
VL - 12
JO - Ecology and Evolution
JF - Ecology and Evolution
IS - 2
M1 - e8554
ER -