Saturday 5 July 2014

Breeding Black Redstarts - July 2014

In Hampshire the Black Redstart Phoenicurus ochruros is considered to be a scarce passage migrant and winter visitor that occasionally breeds, and when it does breed there are usually only low numbers (one or two) of breeding pairs. The UK breeding population according to the BTO 2007 - 2011 Bird Atlas, is currently agreed at between 19 - 44 pairs. It is evident from this information that Black Redstart is a pretty rare breeding bird in Hampshire, so when I was informed of a pair on a private site near Lee-on-Solent, I was keen to check them out to see if the chicks could be ringed in the nest. 

Access to the site was tricky and needed security clearance and I needed to arrange for a Schedule 1 endorsement on my ringing permit, since the species is afforded extra protection whilst breeding. With help from the Dean Swennson who found the birds and the BTO for immediately issuing me with the appropriate endorsement, we were ready to go.

Black Redstart - with Prey

We arrived on site and were immediately watching the two birds going to and from the nest site feeding their young. We watched them for a while and were impressed at how quickly the were able to find prey and return to the nest, it was just continuous. The birds are pretty accustomed to people, since there are plenty around on weekdays, and so seemed unfazed by our presence.

Black Redstart - the darker bird

It was raining occasionally first thing and a bit chilly, so rather than disturb the nest we sat and watched the birds. Normally I would have considered sexing them to be quite easy, but both birds feathers were very worn, and neither bird was showing any evidence of white wing flashes. One bird was darker but it didn't look right for a male.

Black Redstart territory

The territory was located amongst some fairly run down but still used industrial buildings that were constructed of a mix of corrugated asbestos sheeting and block. Opposite these buildings there was a small area of grass and a single oak tree, and this was where the birds were mainly feeding. The grassland was enclosed within a Heras type fence and both birds were regularly using this to spy their prey.

The nest as it turned out was inaccessible. It was located in a live electrical switching unit (see below) which was locked, but partially rusted out. The birds were entering it from the underside where it was badly rusted, but I could not see the nest. It was a real disappointment but there was no way I was going to blindly put my hand into a buzzing box that was connected to mains electricity.

Black Redstart nest location

I had prepared myself well though in case of disappointment and had packed a couple of spring traps and some meal worms. It was obvious where the birds were mainly hunting, so I set the two traps on the ground by the Heras fencing......and almost immediately caught a bird.

Second year presumed male

This was not the bird that I had photographed above, but the other one of the pair and its plumage was in terrible condition. Black Redstarts undergo a complete moult post breeding, with juveniles undergoing a partial post juvenile moult. It was clearly evident, based on the contrast between the brown post juvenile feathers and the blacker adult type, that this bird was a second year bird.

Second year Black Redstart

As if the contrast in the feathers wasn't confirmation enough of age, the wing and tail feathers were also extremely abraded. The tips of the primaries were particularly bleached and worn.

Extremely abraded with feathers

With regards to the tail, all of the feathers were worn but the central pair of feathers were again extremely worn. 

Abraded tail feathers

I presumed that sexing the birds would be easier in the hand since the female should show a well developed brood patch. We didn't catch both of the birds, but this bird showed no evidence of a brood patch and therefore I presumed that it was the male.

Ringed Black Redstart with beak full of prey

After release the bird was straight back into feeding its young, but now seemed slightly more wary of our presence so we sat back and watched from a distance. According to the BTO ringing totals only 43 Black Redstarts have ever been ringed in Hampshire, it would be interesting to know how many of those were pulli. Given that we are now at the beginning of July and the condition of the birds feathers, I wonder if this was their second brood.

No comments:

Post a Comment

Related Posts Plugin for WordPress, Blogger...