Animals that are based on a central place, and head out from their to find food, face an especially daunting problem of finding prey when prey are ephemeral and found in unpredictable places. A new model now shows that colonial seabirds foraging for fish like anchoveta can use social information to help them find their prey. Notably, if outgoing birds track the direction of homeward-bound birds, and follow their path back to their last foraging location, they are more likely to end up in prey-rich places. Once they are there, they can enhance their chances of finding prey if the look for actively feeding birds and search for prey in the same local places. These two strategies greatly enhance the chance of finding prey that might be here today and gone tomorrow. The new research by SAFS research scientist Charlotte Boyd and SAFS Profs George Hunt and André Punt, and their coauthors, appears in the journal Behavioral Ecology.
Which fish are you really eating, and how does that affect conservation?
Up to 30% of the time, the true species being sold or served in restaurants is labeled as something else entirely. A new study gathers data on 43 separate papers that DNA tested fish samples to find the actual species being sold, and compared the truth to the species on the labels. The true species identified by DNA was on average 3% less expensive, but slightly more sustainable than the species listed on the labels. However, this pattern was not consistent: depending on the label, mislabeling could lead to the sale of more endangered species, or it could confer a (counterintuitive) net conservation benefit. The study highlighted cases where mislabeling could be particularly detrimental to conservation efforts and consumers’ pocketbooks. The study was conducted by a group of SAFS graduate students: Christine Stawitz, Margaret Siple, Stuart Munsch, and Qi Lee as part of the one-day-long SAFS research derby, and was published in Conservation Letters.
Revealed: the ups and downs of sablefish
Sablefish are a highly valuable commercial species that inhabit waters as deep as 750 m in the North-East Pacific. New pop-up satellite tag data now show that they do not stick to the bottom all the time: the majority of tagged fish migrate hundreds of meters up and down in the water column every day. The upward migration occurs at night and is likely because the sablefish are chasing their prey of fish, krill and squid, which are migrate vertically. The new work by NOAA scientist Frederick Goetz, and SAFS scientist Andy Jasonowicz and Prof. Steven Roberts, appears in Fisheries Oceanography.
