Chough report: April 2018

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Choughs are now frequently foraging on the southwest tip of Jersey. Photo by Dave Warncken .

by Liz Corry

There is a hashtag floating around the social media stratosphere at the moment, #conservationoptimism, which pretty much sums up this month’s chough report.

When the reintroduced choughs started breeding in the wild in 2015 there were just two males and four females. Three years later we have twelve pairs all eager to contribute to the growing population. Furthermore, two of those pairs have decided to branch out and nest in other parts of the Island.

Nesting ambitions of Jersey’s choughs

A male displaying to his female to encourage ‘sexy time’. The female reciprocating with a suitably unimpressed look. Photo by Elin Cunningham.

We have been able to identify a record number of ten nest sites this year.

Specific details of nest localities will remain guarded in order to protect the pairs. I can, however, let you in on some of the ‘highlights’ we have witnessed in April.

All of last year’s sites in Ronez Quarry are being used again with slight tweaks here and there.

There is concern for Red and Dingle as they are using the nest located on hot piping again. Ronez Quarry are helping us look into ways of raising the nest off the pipes without destroying the integrity of the nest. We wouldn’t want their eggs to overheat like last year.

Red and Dingle’s nest guarantees chicks won’t fall out – providing the eggs survive the heat from pipe work underneath. Photo by Liz Corry.

Dusty has strengthened his bond with Chickay after Egg died and continues to use the upper quarry away from the hubbub of the other nest sites. They have built a very nice nest which should be easy for us to monitor.

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Ronez Quarry with Sark in the background. Photo by Liz Corry.

The first nest located away from Sorel was discovered by one of our zoo keepers on their day off. Anyone visiting Plémont in April will more than likely have heard if not seen a chough or two. In the months leading up to the breeding season we had assumed it was the Les Landes pair. And more often than not it had been. However, on reading the leg rings of the twig-carrying choughs it was clear we had a different pair.

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Plémont Headland. Sorel Point lighthouse just about visible in the background. Photo by Liz Corry.

Finding the nest was a little trickier and not for the faint hearted. It is within the Plémont seabird protection zone which imposes public access restrictions from March to July. Plémont’s cliffs, notorious amongst Jersey’s rock climbers, are described as being ‘Weetabix’ like in structure and to be avoided at all costs. All in all there should be little human disturbance at this site adding to our growing optimism.

Not only is this the first nest discovered away from the release site, it is the first to belong to one of our foster-reared females – Xaviour! She has partnered with a male of her own age, Earl, and as such we are not expecting too much from them. At two-years old they are first timers with no knowledge of exactly what is involved in parenthood.

Regardless, this is a small victory for the project; foster-reared birds can pair up, they can build nests, and not just any nest, a truly wild nest. Fingers (and primaries) crossed for the next few weeks.

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A male chough displaying his ‘excitement’. Photo by Liz Corry.

The record-breaking didn’t stop there. The choughs added a third parish to their tick list of breeding sites. Mary and a wild-hatched male from 2016 were found to have moved roost site 7km to the parish of St Peter. They have been a fairly permanent feature of Simon Sand & Gravel Ltd since last year. Jason Simon, Managing Director, reports seeing three choughs around, but of late one had been ‘pushed out’ by the pair.

Simon Sand & Gravel Ltd located in St Ouen’s Bay is home to sand martins and now choughs too. Photo by Liz Corry.

Two choughs have taken up residence at Simon Sand & Gravel Ltd in St Ouen’s Bay. Photo by Elin Cunningham.

Twigs are visible in the location where the pair roost. It could be a red herring as the site is also used by pigeons. From observations, Mary appear’s quite faithful to that particular spot.

The pair continue making the return trip to Sorel for the supplemental feed. You would assume from this that they are not finding what they need in the wild travelling at least 14km a day for the guarantee of food.

Not so. Thanks to several public sightings, and wonderful photographs, we know that this pair are frequenting Corbière, the southwest tip of the Island.

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Wild-hatched chough hanging out at Corbière 21st April 2018. Photo by Dave Warncken.

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Mary and a wild-hatched chough have become permanent residents of the southwest corner of Jersey. Photo by Dave Warncken.

Funding for nest monitoring awarded by the Ecology Trust Fund.

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We are very proud to receive funding this month from the Ecology Trust Fund.

This is a Jersey-based  fund established in March 1991 by the States of Jersey with a sum of money received in an insurance settlement from the Amoco Cadiz oil tanker disaster of 1978. Annual interest accrued is used to finance multiple projects each year within the environmental sector.

The money will be used to purchase equipment to help the team monitor chough nests around Jersey. Increasingly important as our birds ‘leave the nest’ and set up home around the Island.

Island Insurance Corporation awards

CaptureStaying on a funding and monitoring theme, we are very honoured to hear that Ronez Quarry have nominated the chough project for the Islands Insurance Corporation Conservation Awards. The choughs have frequented the quarry since the trial release in 2013 which is now permanent residence for several pairs.

There are prizes to the value of £1000 and £500 available. If awarded, we will be able to cover the costs of monitoring, ringing, and sexing the wild-hatched chicks. DNA sexing tests, for example, cost £14 per bird.

With 10 potential clutches this year the costs could soon spiral.

Judges will visit the short-listed projects in May after which voting will open for the People’s Choice Award. We will circulate details as soon as voting opens.

Replacement rings

This chough had lost both plastic leg rings. The unique metal ring is impossible to read at a distance. Photo by Liz Corry.

As previously reported, several of the choughs have been losing their plastic rings. Or in the case of Zennor switching them around. As if the team needed more of a challenge to monitor breeding pairs!

On 26th April a group of choughs were caught up at the supplemental feed. Nine of the 25 birds arriving for food were caught up, weighed, and given new replacement rings. White was the only exception in that we had run out of white rings and given grey instead. Off-White if you like.

They all looked to be in good health. None of the females sported brood patches to suggest they had started incubating. I suspect that will have happened towards the end of the month or early May.

We still have two birds requiring replacement rings. They happen to be two of the four now living away from Sorel. Unlikely we wil get them in the aviary anytime soon.

Zoo news

Change is afoot with the Zoo choughs. We are exchanging chough pairs with Paradise Park, Cornwall, as part of our wider departmental collection plan. Paradise Park have kindly agreed to take Lucifer back after loaning him to us in 2012. Hopefully they can address his egg-smashing behaviour.

Jersey Zoo will continue to house two breeding pairs; Tristan and Issy and a new established pair. The move has been delayed until May which will disrupt the breeding season. With a quarantine period of thirty days it is unlikely the new pair will breed at Jersey this year.

Tristan and Issy remain in the Zoo’s on-show aviary and have already started nest building. Keepers found a discarded egg and the nest-liner on the floor of the aviary towards the end of April. Something obviously unsettled them, but they have started gathering wool again to repair their nest.

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Tristan and Issy collect wool to line their nest in the Zoo. Photo by Liz Corry.

Foster rearing might not be on the cards this year

Gianna is making good progress since her cataract operations. It was clear that she had regained sight post-op, but she was not her normal self. At lot was due to a knock in confidence. Living in the dark for several months and then placed in a different enclosure must be disorientating. She also behaved in a way that suggested her depth perception was a little off. Over time she has improved although it could take a couple more months to be fully adjusted.

 

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Gianna enjoying her morning preen. Photo by Liz Corry.

She is now in the off-show foster aviary allowing her to go through the motions of nest-building and such. A great deal of enthusiasm has been expressed although she still doesn’t have a complete nest. By now she would have finished and be eager to start laying.

Tristan and Issy did not need any assistance last year with raising their chick. As the only active breeding pair this year it is unlikely we will need Gianna’s help. Only time will tell.

That, and May’s monthly report!