It is well known that heating the up-per side of an aerofoil decreases the drag induced by air friction, thus making the aerofoil more efficient. It has therefore been speculated that one reason why birds might tend to have darker upper wings is to improve their flight efficiency. This might sound somewhat unlikely, but a recent paper by Svana Rogalla and colleagues provides some evidence for this effect in seabirds (J. R. Soc. Interface 18: 20210236).
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IN AUGUST 2020 the results of the critical vulture nesting survey held annually in Zululand, northern KwaZulu-Natal (KZN), were sobering.
The challenges of photographing in a forest
TOXIC OVERLOAD You are what you eat
Many marine organisms ingest plastic litter at sea, either directly through indiscriminate foraging behavior or indirectly through contaminated prey.
The Cape of Good Hope Nature Reserve, established in 1939, forms a key component of the Table Mountain National Park.
Canon’s RF 100–500mm zoom lens
URBAN PERILS House Sparrows on the decline
Supertramps are species that have spread around the world in as-sociation with humans and they include rats, house mice and a host of weedy plant species.
August sees the greatest flurry of birds at our feeders.
SHAPE-SHIFTING Birds responding to heat stress
Museum collections have always been an essential re-source for ornithological research.
Far & wild
Road-tripping in Namibia
Ringing IN THE Changes
Sandwich Terns in South Africa