Animals that live in groups can affect their populations and ecosystems in complicated ways, so scientists need good methods to measure how many groups there are, how big they are, and how many individuals live in them. Traditional spatial capture–recapture (SCR) methods can estimate either group density or individual density, but they often give biased results for group-living species because […]
From the abstract: “We identified prey capture dives using whale kinematic signatures and found that the probability of capturing prey increased as salmon abundance increased, but decreased as vessel speed increased. When vessels emitted navigational sonar, whales made longer dives to capture prey and descended more slowly when they initiated these dives. Finally, whales descended more quickly when noise levels
Ecologists use spatial capture–recapture (SCR) models to study whole animal populations and movement models to study how individual animals behave. Even though individual movement shapes population patterns, these two approaches have mostly been developed separately. Movement models usually focus only on individuals, while SCR models focus on populations but simplify how animals move. The authors argue that combining these two
Excerpt from the abstract: “Using 34 yr of data from the Magellanic penguin (Spheniscus magellanicus) colony at Punta Tombo, Argentina, we examined the consequences of the delayed onset of breeding (i.e., arrival and egg-laying dates) that has occurred at the colony since 1983. […] We find that delayed breeding has significantly compressed nestling periods at Punta Tombo, influencing chick growth and
The Center for Ecosystem Sentinels invites you to attend an open house in the Boersma Laboratory from 1 p.m. to 3 p.m. on June 7th! Please come see the lab and meet the students. Boersma LabKincaid Annex A0231 p.m. – 3 p.m. At 3 p.m., we will head to Meany Hall for the 3:30 p.m. Awards of Excellence ceremony where
From the abstract: “Our findings, suggesting that female killer whales are at greater risk to close approaches by vessels, highlight the importance of understanding sex-specific responses to disturbance. These findings can inform future management decisions seeking to preserve foraging opportunities and enhance recovery efforts relevant to many cetacean species, including vulnerable and endangered populations.” Authors: Marla M. Holt, Jennifer B.
Identifying the sex of animals is important for conservation and behavior studies, but it can be difficult in species where males and females look similar. In this study, scientists tested simple body measurements to determine the sex of Galápagos penguins without harming them. By measuring features like bill depth and length, they correctly identified the sex of 95% of the
Odile Stern, a New York artist and renowned eclectic collector, donated her penguin collection to the Boersma Chair in Natural History and Conservation at the University of Washington (UW). In February 1987, Ms. Stern, traveled to Punta Tombo as part of volunteer group from UW and the Wildlife Conservation Society to help with penguin research. Every year for a decade,
Full Title: Magellanic penguin telomeres do not shorten with age with increased reproductive effort, investment, and basal corticosterone From the Abstract: “All species should invest in systems that enhance longevity; however, a fundamental adult life-history trade-off exists between the metabolic resources allocated to maintenance and those allocated to reproduction. Long-lived species will invest more in reproduction than in somatic maintenance
Until recently, species from all but three families of seabirds were known to give extended parental care, provisioning young after fledging. The exceptions were shearwaters, storm-petrels, and penguins. The Gentoo Penguin (Pygoscelis papua) is now known to feed its young after fledging. This paper adds the Galapagos Penguin (Spheniscus mendiculus) to the list, describing five instances of adult provisioning of
Laura E. Koehn , Jeffrey J. Hard , Elaine P. Akst , and P. Dee BoersmaThe Auk 133(4):783-805. 2016.https://doi.org/10.1642/AUK-16-50.1 AbstractThe evolution of morphology in a population reflects several factors, including the influence of environmental variability on natural selection. We estimated natural selection on, and heritability of, 4 individual morphological traits (bill length, bill depth, flipper length, and foot length) and
From the Abstract: “Seabirds in expanding colonies select the highest-quality nesting habitat, but habitat selection has seldom been studied in declining colonies. We studied a colony of Magellanic penguins (Spheniscus magellanicus) that declined from 314,000 active nests in 1987 to 201,000 in 2014. As expected, nest quality and reproductive success were higher in burrow habitats than in other habitats, and
The world’s largest breeding colony of Magellanic penguins is seeing unprecedented deaths among young birds. A scientist who has spent 30 years studying the penguins says that climate change is to blame — triggering, among other things, more heat waves and wetter storms that kill fledglings. Source: Changing Climate In Argentina Is Killing Penguin Chicks : NPR
Full Title: Climate change increases reproductive failure in Magellanic penguins Scientists studied nearly 3,500 Magellanic penguin chicks over 27 years to see how weather affected their survival. Starvation was the most common cause of death overall, but in two years heavy rain killed nearly half of all chicks. Predation and starvation happened every year, while storms caused deaths in about
From the abstract: “Forage fish use and value varied and exhibited patterns across latitudes and ecosystem types. Forage fish supported many kinds of predators, including fish, seabirds, marine mammals and squid. Overall, forage fish contribute a total of about $16.9 billion USD to global fisheries values annually, i.e. 20% of the global ex-vessel catch values of all marine fisheries combined.
