First Sperm Whale (Physeter macrocephalus) Record in Mississippi

A sperm whale (Physeter macrocephalus) stranded on the south shore of Horn Island, Mississippi, represents the first record of this species in the state. The specimen, a neonate female, was euthanized at the stranding site. Tissue samples, blood samples, and stomach contents were analyzed following gross necropsy

First Sperm Whale (Physeter macrocephalus) Record in Mississippi

A sperm whale (Physeter macrocephalus) stranded on the south shore of Horn Island, Mississippi, represents the first record of this species in the state. The specimen, a neonate female, was euthanized at the stranding site. Tissue samples, blood samples, and stomach contents were analyzed following gross necropsy

Abundance and Seasonal Occurrence of Cetaceans in Outer Continental Shelf and Slope Waters of the North-Central and Northwestern Gulf of Mexico

Eight aerial line-transect surveys of outer continental shelf and continental slope waters (range 100-2,000 m deep) were conducted seasonally from summer 1992 through spring 1994 in the north-central and northwestern Gulf of Mexico to study the seasonal occurrence and spatial distribution of cetaceans and to estimate their abundances. The surveys sampled an 85,815 km2 study area, resulting in 49,960 km of effort and sightings of at least 18 cetacean species and 365 cetacean groups. Eight species identified in four seasons included bottlenose dolphin (Tursiops truncatus), pantropical spotted dolphin (Stenella attenuata), Risso\u27s dolphin (Grampus griseus), dwarf sperm whale (Kogia sima) and pygmy sperm whale (Kogia breviceps), sperm whale (Physeter macrocephalus), short-finned pilot whale (Globicephala macrorhynchus), rough-toothed dolphin (Steno bredanensis), and Atlantic spotted dolphin (Stenella frontalis). Clymene dolphin (Stenella clymene), striped dolphin (Stenella coeruleoalba), and beaked whales (Mesoplodon spp.) were sighted in three seasons. The number of species sighted seasonally ranged from 10 in fall to 15 in winter. The overall estimated abundance (number of animals) of five species, which accounted for 71% of the identified group sightings, were as follows: bottlenose dolphin, 2,890 (coefficient of variation [CV] = 0.20); pantropical spotted dolphin, 5,097 (CV = 0.24); Risso\u27s dolphin, 1,237 (CV = 0.28); dwarf-pygmy sperm whale, 176 (CV = 0.31 ); and sperm whale, 87 (CV = 0.27). Melon-headed whales (Peponocephala electra) were sighted less frequently but were abundant (2,561; CV = 0.74) because of large group sizes. Common species were widely distributed spatially but occurred in different water depth ranges. In general, species abundance estimates varied seasonally, but the precision of estimates was usually poor (CV \u3e 0.30) and provided little power to detect significant seasonal differences

Distribution of Molidae in the Northern Gulf of Mexico

We compiled all available sighting, stranding and bycatch data for the Family Molidae (molas) in the northern Gulf of Mexico (NGOM) to assess spatial and temporal distribution. Overall, 483 records were collected from shipboard and aerial surveys, fisheries bycatch, and strandings. Molas were recorded year-round, with a ubiquitous distribution in both nearshore and offshore waters. Ocean sunfish (Mola mola) were sighted with greatest frequency during the winter (December thru April) in sea surface temperature \u3c 24° C. Potential reasons for increased sightings during winter may be related to the lack of a well-defined thermocline in the NGOM; the species\u27 basking behavior associated with thermoregulation; and oxygen replenishment after long, deep dives to oxygen-deficient depths

Abundance of Bottlenose Dolphins, Tursiops truncatus, in the Coastal Gulf of Mexico

The abundance of bottlenose dolphins (Tursiops truncatus) for many coastal areas of the United States Gulf of Mexico is poorly known. During spring and fall 1987, we used aircraft and strip transects to estimate bottlenose dolphin abundance within 37 km of the U.S. Gulf shore. Greatest estimated dolphin densities were in the north-central Gulf (spring), northern Florida (fall) and Louisiana study areas (fall) (about 0.30 dolphins / km2). We estimated the coastal U.S. Gulf population of bottlenose dolphins to be 16,892 ± 3,628 (95% Cl) and 16,089 ± 3,338 in spring and fall, respectively. Bottlenose dolphins were found throughout the U.S. Gulf waters searched, but herds offshore of Texas were concentrated near passes and Louisiana herds were more common in and near eastern bays. Our estimates are one of the first assessments of the abundance and density of bottlenose dolphins throughout the coastal U.S. Gulf and may provide useful baseline estimates

Association of Sea Turtles with Petroleum Platforms in the North-Central Gulf of Mexico

A report on the determination of density for five endangered sea turtle species in the vicinity of Gulf of Mexico drilling platforms no longer in use and slated for removal using explosives