Article
Multidisciplinary Sciences
Dennis Brennecke, Magnus Wahlberg, Anita Gilles, Ursula Siebert
Summary: The harbor porpoise in the Baltic Sea is affected mainly by bycatch in static fishing gear, with significant differences in bycatch due to seasonality and region, higher rates in juveniles, and more during a full moon. Understanding these factors can help strengthen conservation efforts for Baltic harbor porpoises.
Article
Biochemistry & Molecular Biology
Phillip A. Morin, Frederick I. Archer, Catherine D. Avila, Jennifer R. Balacco, Yury V. Bukhman, William Chow, Olivier Fedrigo, Giulio Formenti, Julie A. Fronczek, Arkarachai Fungtammasan, Frances M. D. Gulland, Bettina Haase, Mads Peter Heide-Jorgensen, Marlys L. Houck, Kerstin Howe, Ann C. Misuraca, Jacquelyn Mountcastle, Whitney Musser, Sadye Paez, Sarah Pelan, Adam Phillippy, Arang Rhie, Jacqueline Robinson, Lorenzo Rojas-Bracho, Teri K. Rowles, Oliver A. Ryder, Cynthia R. Smith, Sacha Stevenson, Barbara L. Taylor, Jonas Teilmann, James Torrance, Randall S. Wells, Andrew J. Westgate, Erich D. Jarvis
Summary: The vaquita is the most critically endangered marine mammal, with fewer than 19 remaining in the wild. Research has shown that its genome has a stable historical population size and low heterozygosity, potentially allowing for the purging of highly deleterious alleles and maintaining the necessary diversity for population health.
MOLECULAR ECOLOGY RESOURCES
(2021)
Review
Environmental Sciences
Cindy R. Elliser, Anna Hall
Summary: The harbor porpoise in the Salish Sea was once abundant but experienced a significant decline by the 1990s, only to see a resurgence in numbers by the early 2000s. Current research is shedding light on various aspects of their biology and ecology, highlighting the need for continued collaboration to close knowledge gaps and address human threats.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Environmental Sciences
Dimitar Popov, Galina Meshkova, Karina Vishnyakova, Julia Ivanchikova, Marian Paiu, Costin Timofte, Ayaka Amaha Ozturk, Arda M. Tonay, Ayhan Dede, Marina Panayotova, Ertug Duzgunes, Pavel Gol'din
Summary: Bycatch in fishing gear, particularly bottom gillnets and trammel nets, is causing a significant decline in the Black Sea harbour porpoise population. A study conducted from 2019 to 2021 estimated that the annual bycatch of harbour porpoises in the Black Sea ranges from 11,826 to 16,200 individuals. This poses a serious threat to the long-term survival of the population and immediate measures are needed to reduce the bycatch.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Fisheries
Dennis Brennecke, Ursula Siebert, Lotte Kindt-Larsen, Henrik Skov Midtiby, Henrik Dyrberg Egemose, Sara Torres Ortiz, Katrin Knickmeier, Magnus Wahlberg
Summary: This study demonstrates that harbor porpoises exhibit strong avoidance behavior and reduced surfacing frequency in response to pinger sounds, indicating the effectiveness of pingers in reducing bycatch. However, there is also a diversity in behavioral responses, with some porpoises not reacting to pinger sounds at all. This suggests that pinger use should be carefully considered and alternative mitigation measures may need to be explored.
FISHERIES RESEARCH
(2022)
Article
Environmental Sciences
David Lusseau, Lotte Kindt-Larsen, Floris M. van Beest
Summary: Human activities at sea are becoming more complex, requiring adaptable management interventions to mitigate their cumulative effects on biodiversity conservation. Coastal cetaceans, particularly harbour porpoises, are threatened by bycatch and the indirect effects of repeated exposure to disturbances such as acoustic disturbances. The prevalence of pingers, used to mitigate bycatch, can affect both bycatch rate and the population consequences of noise disturbance. Understanding the physiological effects on reproductive decisions and behavioural responses to noise is crucial for evaluating the cumulative impacts of bycatch and its mitigations.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Alexandre N. N. Zerbini, Kimberly T. T. Goetz, Karin A. A. Forney, Charlotte Boyd
Summary: This study used distance sampling to estimate the abundance of harbor porpoises in the Southeast Alaska inland waters, and found that bycatch in the drift gillnet fishery may be unsustainable for the southern population. Monitoring the abundance and bycatch is therefore important for evaluating the potential impact of fisheries on this species in Southeast Alaska.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Marine & Freshwater Biology
Karin A. Forney, Jeffrey E. Moore, Jay Barlow, James Carretta, Scott R. Benson
Summary: This study analyzed the long-term population trends of harbor porpoises in California and found that after the elimination of gill net impacts, the growth rates of the MOR, MRY, and SFRR stocks were 9.6%, 5.8%, and 6.1% per year respectively, with abundance in northern California stable or slightly increasing. This is the first empirical estimate of the maximum net reproductive rate for harbor porpoises.
MARINE MAMMAL SCIENCE
(2021)
Article
Biodiversity Conservation
Lorenzo Rojas-Bracho, Barbara Taylor, Cormac Booth, Len Thomas, Armando Jaramillo-Legorreta, Edwyna Nieto-Garcia, Gustavo Cardenas Hinojosa, Jay Barlow, Sarah L. Mesnick, Tim Gerrodette, Paula Olson, Annette Henry, Henoch Rizo, Eva Hidalgo-Pla, Andrea Bonilla-Garzon
Summary: According to recent research, the population of Mexico's endemic vaquita porpoise is still declining, but the latest survey shows that there are still about 10 adult vaquitas remaining, including calves. Experts speculate that these surviving vaquitas may have learned to avoid gillnet entanglement. However, illegal gillnetting still persists, and the survival of vaquitas can only be ensured by establishing gillnet-free habitats.
ENDANGERED SPECIES RESEARCH
(2022)
Article
Pathology
Lonneke L. IJsseldijk, Meike Scheidat, Marije L. Siemensma, Bram Couperus, Mardik F. Leopold, Maria Morell, Andrea Grone, Marja J. L. Kik
Summary: Bycatch is a significant threat to cetaceans worldwide, with bottom-set gillnets posing a specific risk to harbor porpoises. Methods to assess bycatch rates include on-board observers, electronic monitoring, and fishermen reporting, but systematic approaches are lacking. Necropsies of stranded animals provide insights into bycatch occurrence and health status, but uncertainties remain due to the absence of specific diagnostic tools for underwater entrapment.
VETERINARY PATHOLOGY
(2021)
Article
Ecology
Joanna Dzido, Leszek Rolbiecki, Joanna N. Izdebska, Jerzy Rokicki, Tytus Kuczkowski, Iwona Pawliczka
Summary: This study compared the parasitofauna data of harbor porpoises from the Baltic Proper subpopulation with those from other regions, finding that the Baltic porpoises have a high level of parasitic infection, which might have a negative impact on their health.
INTERNATIONAL JOURNAL FOR PARASITOLOGY-PARASITES AND WILDLIFE
(2021)
Article
Mycology
Hikaru Kanegae, Ayako Sano, Michiko Okubo-Murata, Arata Watanabe, Rentato Tashiro, Takeshi Eto, Keiichi Ueda, Md Amzad Hossain, Eiko Nakagawa Itano
Summary: The research investigated the seroprevalence of specific fungi in Dall's porpoises and harbor porpoises stranded in Hokkaido, Japan, revealing positive seroprevalence of these fungi in cetaceans living in cold waters.
Article
Agriculture, Dairy & Animal Science
Aleksija Neimanis, Jasmine Stavenow, Erik Olof Agren, Emil Wikstrom-Lassa, Anna Maria Roos
Summary: This study examined the pathology and causes of death in stranded harbour porpoises from Swedish waters. The most common cause of death was bycatch in fishing gear, followed by disease, mainly pneumonia. The presence of bacteria with zoonotic potential in the porpoises was documented for the first time in Swedish waters. The results provide important reference for monitoring the health and disease patterns of porpoises and their environments.
Article
Multidisciplinary Sciences
Ciska Bakkeren, Michael Ladegaard, Kirstin Anderson Nansen, Magnus Wahlberg, Peter Teglberg Madsen, Laia Rojano-Donate
Summary: The dive response in marine mammals allows them to adapt their oxygen consumption to breath-hold duration and depth by adjusting peripheral vasoconstriction and heart rate. A study on a trained harbor porpoise showed that it halves its diving heart rate when blindfolded, indicating that sensory deprivation can enhance the dive response. This suggests that visual stimuli may play a more significant role in echolocating toothed whales than previously believed.
Article
Agriculture, Dairy & Animal Science
Lembi Lougas, Valdis Berzins
Summary: Research in the eastern Baltic Sea has found evidence of Stone Age coastal communities using harbor porpoise bones to decorate pottery vessels. This suggests that the high salinity of the Baltic Sea at the time made it a favorable environment for the porpoise. Compared to seals, the harbor porpoise has received less research attention in the Baltic Sea.