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Patrick J. Gould

Publications and source records attributed to Patrick J. Gould.

7 recordsLinked to original sources
USGS2016

Food of Flesh-footed shearwaters Puffinus carneipes associated with high-seas driftnets in the central North Pacific Ocean

We examined digestive tract contents and stable nitrogen isotope ratios in breast muscles of Flesh-footed Shearwaters Puffinus carneipes associated with high-seas driftnet fisheries in the central North Pacific Ocean. Small fish, Lanternfish (Myctophidae) and Pacific Saury Cololabis saira , were the principal prey found in the digestive tracts. Pieces of unidentified fish, possibly Pacific Pomfret Brama japonica , and shredded squid tissue, mostly Neon Flying Squid Ommastrephes bartrami , in the digestive tracts indicate scavenging at driftnet fishing operations. Although soft-bodied animals such as Velella sp. were rare in the digestive tracts, low stable nitrogen isotope values (δ 15 N) suggest Flesh-footed Shearwaters feed heavily on such low trophic level animals.

Emu↗
USGS2000

Foods, trophic relationships, and migration of Sooty and Short-tailed Shearwaters associated with squid and large-mesh driftnet fisheries in the North Pacific Ocean

We salvaged dead birds from high seas driftnets in the Central North Pacific Ocean during a study of the impact of high seas driftnet fishing on marine ecosystems. Digestive tract contents and stable isotopes of nitrogen and carbon in breast muscles of these birds were analyzed to assess the effect of driftnets on the trophic relationships of marine birds. The diets of Sooty ( Puffinus griseus ) and Short-tailed ( P. tenuirostris ) Shearwaters associated with high seas driftnets in the transitional region of the North Pacific Ocean overlap broadly. The principal differences between them include 1) Sooties prey more heavily on immature stages of invertebrates, especially the barnacle Lepas fascicularis than do Short-tails, 2) Pacific saury ( Cololabis saira ) are the primary fish taken by Sooties while lanternfish ( Myctophidae ) are the primary fish taken by Short-tails, and 3) Sooties take a wider variety of prey than do Short-tails. During the last years of extensive high seas driftnet fishing (early 1990's), both shearwaters augmented their diets with about 15% offal and discards from fishing vessels. Values for stable isotopes of nitrogen and carbon in breast muscle tissues (δ 15 N and δ 15 C) indicate the extent and timing of movements of Sooty Shearwaters: including arrival of migrants from the south Pacific (April-May), east to west movement from the eastern Pacific (May-June), and west to east movement from Japan (August-September). Fall migrant Sooties were not detected. The only movements of Short-tails that we detected were a few south-bound migrants in September-November.

Waterbirds↗
USGS1997

The highest global concentrations and increased abundance of oceanic plastic debris in the North Pacific: Evidence from seabirds

Plastic pollution has risen dramatically with an increase in production of plastic resin during the past few decades. Plastic production in the United States increased from 2.9 million tons in I960 to 47.9 million tons in 1985 (Society of the Plastics Industry 1986). This has been paralleled by a significant increase in the concentration of plastic particles in oceanic surface waters of the North Pacific from the 1970s to the late 1980s (Day and Shaw 1987; Day et al. 1990a). Research during the past few decades has indicated two major interactions between marine life and oceanic plastic: entanglement and ingestion (Laist 1987). Studies in the last decade have documented the prevalence of plastic in the diets of many seabird species in the North Pacific and the need for further monitoring of those species and groups that ingest the most plastic (Day et al. 1985).

Book chapter↗
USGS1993

Population dynamics of the Laysan and other albatrosses in the North Pacific

Laysan albatrosses ( Diomedea immutabilis ) are among the most prominent bird species which interact with commercial fisheries in the North Pacific. They are attracted to fishing nets and vessels and feed extensively on animals caught in nets, waste fish, offal, and refuse discarded from vessels. Approximately 17,500 individuals were killed in the five major high seas driftnet fisheries in 1990. Laysan albatross numbers are still increasing after being decimated in the early 1900's. Mortality in the high seas driftnet fisheries is reducing the recover rate by an estimated 0.4 to 1.6% per year depending on the intrinsic growth rate of the population. The impact of the fisheries is thought to be more severe on the less abundant black-footed albatross ( Diomedea nigripes ) which is also increasing but at a lower rate. No driftnet mortalities have been reported for the short-tailed albatross ( Diomedea albatrus ).

Bulletin of the International North Pacific Fisher↗
USGS1989

Techniques for shipboard surveys of marine birds

We describe shipboard and small boat techniques used by the US Fish and Wildlife Service in Alaska to survey marine birds at sea. The basis is a 10-min, 300-m-wide, strip transect taken from a platform moving at a constant speed in a constant direction. Special routines, such as instantaneous counts of traveling birds, are explained to help reduce biases caused by factors such as varying flight patterns, ship-following and avoidance, and patchy distributions. Data recording and coding techniques and formats, based on those developed for the National Oceanic Data Center, are described.

Fish and Wildlife Technical Report↗
USGS1983

Seabirds between Alaska and Hawaii

Seabirds were observed between Alaska and Hawaii along 158°W longitude from 24 October to 6 November 1976. Their distributions and abundances corresponded remarkably well to oceanographic regions. Indices of seabird density dropped in a series of plateaus from 44 birds/km 2 in the Alaska Current System to less than 1 bird/km 2 in subtropic waters. Northern distribution records were found for six species. The Subarctic Boundary marked the center of the separation between subarctic and subtropic pelagic avifaunas.

Alaska, Hawaii↗