Captive breeding - Birds on the edgeBirds on the edge

Aims The vision for the restoration of Jersey’s coastal avian biodiversity looks 10-20 years into the future. The reintroduction of choughs into Jersey is seen as the driving force in achieving this vision and to undertake this we need to manage a captive population to provide us with donor stock. The initial captive management plan will focus on the first 5-7 years in order to establish a viable population of choughs in captivity in Jersey and to trial their release into the wild. This plan will be monitored closely and evaluated as it progresses. For the management plan to succeed it needs to meet several objectives:

To establish and manage a viable captive population and ensure maximum genetic diversity
To provide captive-reared individuals to trial their release in order to establish the correct methods needed to develop a free-ranging population in Jersey
To promote public awareness of coastal restoration and farmland ecology through educational opportunities using the chough as a flagship species
To develop research opportunities to maximise understanding of captive-husbandry and breeding of choughs
To develop best practice methods for captive-breeding and reintroduction of a social birds that can be applied elsewhere to future conservation projects
To produce a husbandry manual on the management techniques needed to guarantee successful re-introductions of choughs and related birds elsewhere.

Information on the chough can be found on the Factsheet Read updates and monthly reports on the captive project Aviary requirements for captive breeding Keeping the choughs at Durrell requires aviaries to accommodate breeding pairs, pre-release birds and birds for public display. Choughs flock together out of the breeding season and/or as juveniles and this allows for some flexibility and reduces the need for individual aviaries to hold birds throughout the year. The minimum housing requirements at Durrell are: 3-5 off-public show breeding aviares Breeding aviaries are simple high-framed, long units with minimal decor. Shelving with rocks emulates cliff tops. Nest-boxes with camera units for nest monitoring with minimal disturbance are fitted to walls. Breeding is more successful if disturbance from keepers and public is kept to a minimum and these aviaries need to be off show, possibly even away from roads, public access paths, and other animal enclosures so noise levels are relatively low. Keepers only access the aviaries once a day and use nest-box cameras to remotely check nests. 1-2 off-show flocking aviaries Non-breeding birds are flocked together as they would be in the wild (July-March). These aviaries have also been used for conditioning and training birds prior to release. Since early 2013 all birds destined for release have been moved quickly to the release site on Jersey’s north coast as it is more convenient if newly imported birds are quarantined here close to their new home. Display aviary The display aviary is essentially a large flocking aviary, but primarily acting as an educational tool for promoting awareness for the coastal restoration project and the chough release. The display aviary can also be used for social training and conditioning. What the choughs eat In captivity the choughs are given their breeding season diet given from the end of February until August. During this period they receive more protein than during the winter. The main diet is made up of mincemeat, universal food (a shop-bought food for birds), grated egg and eggshell (for calcium), grated carrot and breadcrumbs. In the breeding season we add finely chopped heart for extra protein and cuttlefish powder for extra calcium Daily routine In the morning we visit the aviaries and give the birds some insects (typically mealworms spread onto the ground) and give them fresh water. They have their main meal around midday followed by two afternoon visits when more insects are spread on the ground for the birds to find. They are given a variety of insects, mostly bought in such as mealworms, crickets and waxmoth larvae. We grow our own beetles from the shop-bought mealworms. Then we try our best to provide them with wild insects mainly ants and ant larvae and woodlice. The ants are highly favoured by the adult choughs to feed their chicks so we have to hunt for ant nests in the breeding season. Every few days we turn over rocks and log piles in the aviaries which naturally harbour insects so that the birds can pick them out. Daily management is still relatively straight forward during the breeding season when we also monitor the nests via the nest cameras. Nesting and egg-laying Chough pairs in the Wildlife Park have laid eggs from March to May each year since 2010 (see Monthly Reports). Although we had some hatches it was not until 2014 that four chicks were successfully reared (May 2014 report). These first chicks, from two adult pairs, were hand-reared and joined the other birds at Sorel. Summary Captive-breeding facilities at the Durrell’s headquarters in Trinity in partnership with Paradise Park in Cornwall, will manage a captive population of red-billed choughs in order to produce sufficient birds to establish a free-living population in Jersey. Birds displayed at Durrell will become a focus for presenting the species to the public and a tool for education and awareness. Budget Costs for the captive-breeding project at Durrell include: