Hunting and social behaviour of leopard seals (Hydrurga leptonyx) at Seal Island, South Shetland Islands, Antarctica

The hunting behavior of leopard seals Hydrurga leptonyx was monitored opportunistically at Seal Island, South Shetland Islands, during the austral summers from 1986/87 to 1994/95. Leopard seals used several methods to catch Antarctic fur seal pups Arctocephalus gazella and chinstrap penguins Pygoscelis antarctica, and individuals showed different hunting styles and hunting success. One to two leopard seals per year were responsible for an average of 60% of observed captures of fur seal pups. Leopard seals preyed on penguins throughout the summer, but preyed on fur seal pups only between late December and mid-February. Hunting behavior differed significantly between different locations on the island; fur seals were hunted only at one colony, and penguins were hunted in several areas. The relative abundance of prey types, size of prey in relation to predator, and specialization of individual leopard seals to hunt fur seal prey probably influence individual prey preferences among leopard seals. On five occasions, two leopard seals were seen together on Seal Island. Possible interpretations of the relationship between the interacting leopard seals included a mother-offspring relationship, a consorting male-female pair, and an adult leopard seal followed by an unrelated juvenile. In two incidents at Seal Island, two leopard seals were observed interacting while hunting: one seal captured fur seal pups and appeared to release them to the other seal. Observations of leopard seals interacting during hunting sessions were difficult to confirm as co-operative hunting, but they strongly implied that the two seals were not agonistic toward one another. The hunting success of individual leopard seals pursuing penguins or fur seals is probably high enough for co-operative hunting not to become a common hunting strategy; however, it may occur infrequently when it increases the hunting productivity of the seals.

Predator-induced stress makes the pesticide carbaryl more deadly to gray treefrog tadpoles (Hyla versicolor)

Global declines in amphibians likely have multiple causes, including widespread pesticide use. Our knowledge of pesticide effects on amphibians is largely limited to short-term (4-d) toxicity tests conducted under highly artificial conditions to determine lethal concentrations (LC50). We found that if we used slightly longer exposure times (10–16 d), low concentrations of the pesticide carbaryl (3–4% of LC504-d) killed 10–60% of gray treefrog (Hyla versicolor) tadpoles. If predatory cues also were present, the pesticide became 2–4 times more lethal, killing 60–98% of tadpoles. Thus, under more realistic conditions of increased exposure times and predatory stress, current application rates for carbaryl can potentially devastate gray treefrog populations. Further, because predator-induced stress is ubiquitous in animals and carbaryl's mode of action is common to many pesticides, these negative impacts may be widespread in nature.

Canadian wilds : tells about the Hudson's Bay Company, northern Indians and their modes of hunting, trapping, etc. /

Mode of access: Internet.

The archaeology of Standing Rock overhang : a long-term record of bighorn sheep hunting and processing in southeastern Idaho /

Mode of access: Internet.

Stamp hunting /

Mode of access: Internet.

The Woodmont story; hunting and fishing and raising wild turkeys in a sportsman's paradise.

Mode of access: Internet.

Complete book of hunting,

At head of title: Outdoor life.

Migratory-bird hunting stamp : hearings before a subcommittee of the Committee on Agriculture, House of Representatives, Seventy-third Congress, second session, on H.R. 5632. January 31, 1934.

Mode of access: Internet.

The outdoorsman's handbook (formerly The angler's guide) : a book of useful facts and figures on the technology of the outdoors, for the hunter, angler and wilderness traveller, including the game laws and fishing and hunting resorts for the current year.

Includes index.

News hunting on three continents /

Includes index.

Energy and nutrient dynamics of predator and prey arthropod populations in a grassland eco-system

Based upon a dissertation by R. I. Van Hook to the Graduate Council of Clemson University in partial fulfillment of the requirements for the degree of Doctor of Philosophy.

Predator control - why and how,

Mode of access: Internet.

The sportsman's cyclopaedia : comprising a complete elucidation of the science and practice of hunting, shooting, coursing, racing, fishing, hawking, cockfighting, and other sports and pastimes of Great Britain, interspersed with entertaining and illustrative anecdotes /

Extra numbered pages: 183*-184* and 191*-196* inserted.

Bird hunting on the White Nile; a naturalist's experiences in the Soudan.

Appendices: A. List of the birds collected and observed.--B. List of the mammals.

A study of predator control on Valcour Island.

Pittman-Robertson project 1-R, Supplement 1.