Nearly 1 700 abandoned Cape cormorant chicks have been rescued from Robben Island for admission to SANCCOB (the Southern African Foundation for the Conservation of Coastal Birds) in Table View, Cape Town in the last two days (SUBS: Tues 12 & Wed 13 January). A robust rescue operation was executed by Robben Island Museum (RIM), SANCCOB, the Two Oceans Aquarium and the NSRI (National Sea Rescue Institute) to retrieve and safely transport the chicks, which have been abandoned by their parents and are too young to fend for themselves.
The estimated 3,000 breeding pairs of Cape cormorants on the island usually each hatch two to three chicks each summer, so the abandonment put thousands of chicks at risk. This rescue operation is likely to be the second-biggest seabird rescue in the Western Cape, since the MV Treasure oil-spill in 2000.
On admission to SANCCOB’s seabird hospital, each chick was weighed and hydrated to quickly stabilise it and reduce its stress, then placed in designated pens according to its weight. A complete veterinary assessment was then conducted on each chick. Sadly, a small number of birds could not be saved in time, but the vast majority – nearly 1 700 chicks, each weighing between 150g to 600g – are being cared for.
SANCCOB’s researchers suspect lack of food to be the main reason for the abandonment, but investigations are still underway. Dr Katta Ludynia, SANCCOB’s Research Manager says, “Cape cormorants feed mainly on anchovy, and to a smaller extent, on sardines, and these small pelagic fish species are at very low levels at the moment.
“We are seeing dramatic population declines in all seabird species that rely on these fish species: the African penguin, the Cape gannet and Cape cormorant are all listed as endangered by the International Union for Conservation of Nature (IUCN) and lack of sufficient food is the primary factor for the most recent declines observed.”
It was initially suspected that adult birds had begun flying out to sea to cool down during the hot weather of the last two days. But Dr Ludyinia says that had this been the case they would have been seen rafting (floating in groups) close to the island and eventually return to their chicks when the temperature dropped.
She explains, “Cape cormorants are summer breeders: their main breeding season is between October and December and they breed along the coast of South Africa and Namibia, into Angola, so they should be used to heat. A recent study on the behaviour of Cape cormorants and other cormorant species did not observe abandonment at high temperatures comparable to what we had in recent days.”
Dr Ludyinia says the high survival rate of the rescued chicks is a result of speedy, coordinated action by all concerned: SANCCOB and RIM’s penguin and seabird ranger monitors the birds on the island – amongst other duties – and immediately alerted RIM’s Environmental Unit and SANCCOB when adult cormorants did not return to their chicks after a few hours.
The NSRI’s Table Bay station immediately responded to the rescue parties’ request for assistance. The chicks were boxed and transported to the mainland by NSRI’s sea rescue craft, Spirit of Vodacom.
Mr Thabo Seshoka, Robben Island Museum’s Head of Heritage and Research, concurs that the abandonment is unusual, and that quick intervention helped ensure the birds’ best chance of survival: “It’s an anomaly that both RIM and SANCCOB are studying. Annually, 186 bird species (including the endangered African Penguin) breed on the Island, which underpins the need for responsible tourism on the island, which is a Marine Protected Area and World Heritage Site.”
“Conservation is central to the Robben Island Museum’s mandate as a museum. Although the island was proclaimed a World Heritage Site in 1999 under the category of cultural landscapes, fauna and flora form part of our valuable heritage assets and must be prudently conserved and sustained at all times. We appreciate our collaboration with SANCCOB as it bolsters our efforts in managing the island as an integrated resource.”
SANCCOB is focusing on providing the veterinary and rehabilitative care for the cormorant chicks until eventual release, while simultaneously rehabilitating other, existing seabird patients. In light of this crisis situation, SANCCOB will need the support of public to help in their fundraising endeavours to contribute to medication and fish for the chicks.