KILLER WHALES, ORCINUS ORCA, IN THE SOUTHEASTERN BERING SEA: RECENT SIGHTINGS andPREDATION ON OTHER MARINE MAMMALS

An unusual number of killer whales appeared in inshore waters of the southeastern Bering Sea in summer 1989 and 1990. Multiple sightings occurred in Bristol and Kuskokwim bays where killer whales had been seen only rarely in previous years. Three animals became stranded on mud flats in Kuskokwim Bay but were able to free themselves on a high tide. Killer whales were observed interacting with salmon, harbor seals, Steller sea lions, walruses, and beluga whales. Detailed observations were made of killer whales attacking belugas in the Naknek River. Local conditions and behavioral adaptations may reduce the susceptibility of belugas to killer whale predation. Continued killer whale activity in this area would be unlikely to affect fish resources, but might have some influence on beluga whales.     

NOTES ON BIRDS IN THE GAMBIA

Recent observations in The Gambia have shown that the status of many species has changed in the last forty or fifty years and have provided data on the local breeding seasons for a number of birds. Several species have been found for the first time in this part of West Africa. The various birds concerned are given in a systematic list, together with notes on all the Palaearctic migrants so far recorded from The Gambia. Organized research is recommended on several lines: on the sequence of food sources, especially through the long and severe dry season, when Palaearctic birds are added to resident and when some African species breed. The bird ecology of the mangroves remains to be worked out, and also the relative importance to birds of cleared ground and untouched "bush" at all seasons.     

THE BREEDING SEASONS OF AFRICAN BIRDS—2. SEA BIRDS.

1. All the available data, largely unpublished, are assembled for sea-birds breeding in African waters, about 36° N.-36° S.
2. An ill-defined breeding season by any species at any station is exceptional.
3. North of the Equator practically all sea-birds breed in spring or summer.
4. South of the Equator there is much more variation. Round the Cape there is a good deal of mid-winter breeding, mainly in stations affected by the warm Agulhas current.
5. On the east coast most of the breeding takes place in the period June–August from the Gulf of Suez (27° N.) to the mouth of the Zambesi (19° S.) and beyond, i.e. in the hottest months north of the Equator and the coolest months south of it.     

SPATIAL AND TEMPORAL ABUNDANCE PATTERNS OF WATERBIRDS IN THE SOUTHERN CAPE PROVINCE. PART 3: WADING BIRDS

Boshoff, A.F., Palmer, N.G. & Piper, S.E. 1991. Spatial and temporal abundance patterns of water-birds in the southern Cape Province. Part 3: Wading birds. Ostrich 62:197-214.

Wading birds (herons, egrets, spoonbills, flamingoes and waders) were counted, and water-level and water transparency measured, on a monthly basis from 1980 to 1983 or 1984, at the six waterbodies comprising the Wilderness-Sedgefield Lakes Complex, southern Cape Province. The fluctuating status of the submerged aquatic macrophytes, and the trophic status of the waterbodies, was documented. The counts reflect the monthly status of the birds, and allow the calculation of densities (birds/ha). Linear and logarithmic models aided the interpretation of the count data. Spatial and temporal patterns and trends are described, and discussed in relation to changes in water-level, water transparency and aquatic macrophyte biomass regimes in the study area. Water-level was an important environmental parameter and was generally negatively correlated with abundance.