The female pink pigeon, who laid her eggs had recently arrived from America to the Zoo’s sister attraction, Wild Place Project, in the hope she would pass on her valuable genes. However, she was proving to be unreliable at incubating her own eggs.
Keepers from both attractions made the decision to transfer her eggs from Wild Place Project to Bristol Zoo Gardens, where a colony of domestic Barbary doves had been established for this eventuality.
The use of foster doves was an intentional management strategy to increase production and bolster the European captive population.
One by one, each egg was delicately transported in a portable incubator to ensure optimal temperature. Upon arrival, each pink pigeon egg was substituted for an egg being incubated by a pair of Barbary doves – the new foster parents seemingly unaware of the switch.
After hatching, the foster parents fed the pink pigeon chicks as if they were their own, despite them growing to be larger and a different colour to themselves.
In total, four pink pigeons were raised by different pairs of Barbary doves. In a further twist, the fifth youngster was raised by another threatened species – a pair of Mindanao bleeding heart doves which originate from the Philippines.
Will Walker, animal manager at Wild Place Project, said: “Like all pigeons, it’s not unusual for some pink pigeons to be distracted from their parental duties. However, each egg is incredibly precious and, crucially, each chick represents valuable genetic diversity for the species.”
Richard Switzer, Curator of Birds at Bristol Zoo, added: “It has been a great collaborative effort between both teams at Wild Place Project and Bristol Zoo. But the collaboration extends further. As part of a coordinated effort between European Zoos and the Mauritian Wildlife Foundation, we hope that the offspring of these birds might return to Mauritius, to give the wild population a valuable boost.
“If only our domestic doves knew the valuable role they were playing in the conservation effort.”
The island of Mauritius is located around 2,000km off the southeast coast of Africa, and was notably the home of another pigeon, the dodo.
In the early 1990s, the pink pigeon population had declined to less than 20 birds remaining in the Mauritian forests.
Following a successful captive breeding and reintroduction programme, coupled with the hands-on management of the pigeon’s fragile island ecosystem, the wild population has rebounded to 500 birds.
Recent studies have shown that some of the genes of the European and American captive populations are unrepresented in this wild population. Lack of genetic diversity in a population accentuates the threats it may face; for example, it may reduce a population’s ability to resist a particular disease, or may reduce the hatching success of eggs. This demand for valuable genes to return to Mauritius is what underpins the Wild Place Project / Bristol Zoo Gardens collaboration.
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