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Study of winter movements of Black Brants in Mexico and southern California, USA, revealed that movement probabilities were negatively related to distance between winter sites, both within winters and between winters. Southward movement exhibited between winters was influenced by variation in habitat quality and a northward movement exhibited by them between months in winter was related to migration patterns.

Research undertaken at Izembek Lagoon on the Bering Sea close to the end of the Alaska Peninsula into the response of fall-staging brant and Canada geese to aircraft overflights established that 75% of the brant flocks flew in response to aircraft overflights. Brant response to aircraft at different altitudes was inconsistent. Canada goose flocks hardly ever flew in response to fixed-wing or rotary-wing aircraft. Lateral distance between aircraft and flock was the most significant parameter in anticipating response of brant and Canada geese to overflights.

The behavioral responses of Pacific brant and Canada geese to aircraft overflights in southwestern Alaska during fall staging were investigated. Predictive models of brant and Canada goose response to aircraft altitude, noise, type and lateral distance from flocks were developed for this purpose. Results showed that a significantly higher number of brant flew in response to overflights than did Canada goose flocks. The implications of the findings for wildlife management were discussed.

Researchers surveyed Pacific brant six times annually over seven years from 1987. The objective was to gain understanding into why the number of nesting birds had fallen by 34% since 1961. The researchers resighted banded birds at a large Alaskan colony during major annual events, including spring migration and nesting, taking account of subsistence harvest and sport harvest periods. The surveys revealed that the lowest survival rate occurred in the late spring migration, and the researchers concluded that subsistence harvesting has an important impact on brant survival rates.

Researchers tested the data obtained in surveys of black brant geese to analyse the effects on mortality rates of capturing and handling the geese during banding procedures. They concluded that handling produced no bias. This was consistent with their hypothesis that individual birds which were more sensitive to handling would have a higher probability of death from other causes. The researchers used the SURVIV program with an ultrastructure approach to analyse the data.

The effects of harness-attached radio transmitters on the reproductive capabilities of migratory birds was studied on female brants. The study evaluated the effects of 35-gram back mounted transmitters attached with ribbon harnesses and 26-32-gram back mounted transmitters attached with plastic-coated wire harnesses. Between 1987-89, the number of brants with transmitters that returned to breed was the same as those without transmitters. Between 1988-92, however, the number of brants with transmitters that returned were lower than those with transmitters.

A study of natural and human disturbances to migrating brants at the Izembek Lagoon, Alaska, showed that brants responded to 67% of all disturbances including disturbances from aircraft and boats. The bald eagle created the greatest disturbance to the brants.