Durban - When their dads go hunting, leaving moms at home, African crowned eagles not yet ready to leave nests in urban Durban are more likely to have monkey on the menu, University of KwaZulu-Natal research has found.
According to a paper prepared by Professor Colleen Downs and Shane McPherson of the university’s School of Life Sciences, and Tim van der Meer from the University of Amsterdam in the Netherlands, adult male birds have been doing most of the hunting for their young, especially at the start of the nestling period.
“This may be caused by changing requirements of nestlings,” it read.
“Adult males did most of the food provisioning, especially at the start of the nestling period.”
Other items commonly on the nestlings’ menu were dassies and hadedas.
According to the researchers, the increase in catching monkeys by crowned eagles indicated an increase in larger prey being delivered to the nests as the nestling aged.
“We suggest that this
could be caused by increased participation in hunting by the larger female as her nest attendance time decreased as the nestling aged.”
Relatively little was known about African crowned eagle nestling diet, especially about how it changed with nestling age, so the researchers investigated this with nest camera-traps.
The study concluded that it is important to protect the Durban Metropolitan Open Space System (D’MOSS) zones for the sake of the near-threatened African crowned eagle along with its choice of food to make sure that it can breed healthily.
Another paper showed that African crowned eagle breeding sites in the city limits were not evenly distributed and closely associated with natural forest, while nest trees were most frequently in patches of exotic large riverine Sydney blue gum within the D’MOSS planning zones.
“Crowned eagles showed a strong tendency to avoid informal settlement areas; however they were tolerant of proximity to established formal settlements and occupied dwellings,” read the paper,
this time compiled by Downs, McPherson and Mark Brown, also from UKZN’s School of Life Sciences, at its Pietermaritzburg campus.
Another study from the institute showed that the suburban swing of Kloof and Hillcrest suits large spotted-genets.
When residents aren’t feeding them pieces of chicken and other meat, they’re treating pet bowls like fast food outlets. However, some residents fear their presence has a negative impact on birds and that the genets could be carriers of rabies.
The urbanised large-spotted genets have also found urban enemies that cross their
paths: domestic dogs and fast-moving cars.
According to the genet researchers - Downs, Craig Widdows and Dr Tharmalingam Ramesh - the felines have also taken to using warmer roofs as daytime roosts instead of their usual tree hollows and canopies.
This has affected their breeding patterns, giving the Upper Highway large-spotted genet world a baby boom in the cooler months.
And cockroaches have become a characteristic of rooftop cuisine.
“Small mammals also formed an important component of the diet,” read a report.
Wetland-living African woolly-necked storks have also become urban migrants, according to yet another School of Life Sciences report by Downs and Vuyisile Thabethe.
And they are welcome newcomers throughout Durban and Pietermaritzburg.
“We found that a significant number of householders fed African woolly-necked storks on a daily basis throughout the year.”
There was a year-round presence of the birds, contrary to the perception that they would all have migrated to other parts of the world for winter.
People who said they fed the storks said they did so by providing meat, while others provided inappropriate food such as bread.
The report recommended that suitable guidelines be put together to show humans how to feed their fellow urban African woolly-necked storks more appropriately.