The Southwest Fisheries Science Center (SWFSC) has conducted a variety of marine mammal surveys in the eastern tropical Pacific (ETP) and other areas of the Pacific Ocean. The purpose of these surveys has been to estimate cetacean population sizes and to monitor the impact of incidental kill due to commercial fisheries, particularly the tropical purse-seine fishery for yellowfin and skipjack tuna. The northern stock of common dolphin, Delphinus delphis, is taken in the purse-seine tuna fishery (Hall and Lennert 1994). The index of relative abundance for this stock computed from sightings on tuna vessels has declined substantially in the last decade (Anganuzzi and Buckland 1994). However, because tuna vessels cover only the southern portion of the stock’s range, the declines in the index may be due to a northward shift in distribution, rather than an actual decline in abundance. There has been an increase in abundance of tropical delphinids and a decrease in abundance of temperate delphinids during this period in California waters, accompanied by a general warming trend in ocean temperature (Barlow, 1993). Previous research vessel surveys have covered either northern (Hill and Barlow 1992) or southern (Wade and Gerrodette 1993) parts of the range of the northern common dolphin, but neither of these surveys have covered the middle portion of the range off the coast of northern Baja California. The 1993 survey was designed to produce the first range-wide estimates of abundance for the northern common dolphin and its recently described congener, Delphinus capensis (Heyning and Perrin, 1994) . The 1993 survey was conducted by the NOAA Ships McArthur and David Starr Jordan.
Length distribution of a subset of individuals from a species (mainly non-target) caught during SWFSC-FRD fishery independent trawl surveys of coastal pelagic species. Measured lengths for indicated length type (fork, standard, total, or mantle) were grouped in 10 mm bins (identified by the midpoint of the length class) and counts are recorded by sex. Does not include species with individual lengths recorded in the CPS Trawl Life History Specimen dataset.
Data were collected from several penguin monitoring sites in the Antarctic peninsula region, the South Orkney Islands, and East Antarctica between 1977 and 2017 using traditional and autonomous methods.Traditional methods consisted of researchers conducting direct observations of penguins throughout the season to record information on egg laying, incubation, and brood/guard periods. Simultaneously, autonomous methods consisted of time-lapse cameras deployed at the penguin colonies to photographically record the same daily nesting activities throughout the season. Seabirds observed in this study are Adélie (Pygoscelis adeliae), chinstrap (P. antarctica), and gentoo (P. papua) penguins.