Wednesday, 19 August 2020

House Sparrows

Having your local ringing site go up in flames while 'locked down' means that you either stop ringing or look elsewhere for a potential project or area of study. A garden CES was out of the question as we are still quite busy restructuring the lower part of our garden. Over the last couple of years it hasn't been unusual to see a flock of up to 60 House Sparrows hanging around the house from July to September waiting for some seed to be put out. Rather casually I had estimated that there were perhaps 15-20 pairs of House Sparrows in the village and had considered this too few for a RAS study. This year during the spell of fine settled weather, I watched the House Sparrows using my nest boxes and was quite surprised at how good the adult birds were at catching insects and how persistent they would be if the initial surprise attack failed; often sitting on a gutter or similar raised perch and then descending to the ground in a direct dive to catch prey. I also watched activity at the nest boxes and observed on several occasions the aggression of a male towards his mate if she returned to the nest with food but didn't enter the box immediately. On the days when the weather was not so good, the birds would focus more on my feeding areas. Having made my early observations, I removed one aerial feeder, introduced a second table to where the birds seemed to prefer to congregate, carried out a little pruning and set positions for several nets. It is now mid August and the season appears to have been a productive one with third brood juveniles on the wing the first of which are starting to moult. One of my net positions was a waste of time for House Sparrows but caught lots of Dunnocks. Another has produced an ear shattering 24 different Great Spotted Woodpeckers but I have stuck with it because it has also been the most productive net for House Sparrows.

From the 1st of April until the 17th of August, at least 355 different House Sparrows have been in and out of my nets and boxes. 40 of these have been adult males and 32 adult females. As I fed the birds this morning, I could see several adults along with many first year birds that have avoided capture during the last four and a half months. So, my initial estimate of the number of pairs was obviously far too casual. I know for certain that not all of the male birds were paired during the window of the first two broods with some males not attracting females to their nests. I also know that at least one of these unpaired males mated with a female on several occasions; he remined at his 'post' while she went elsewhere but was not traced. 

If I assume that a more realistic number of pairs is 40; 2 chicks per nesting attempt would give rise to 240 young and 3 chicks per attempt 360 young. I think that it would be safe to assume that the village/surrounding area is probably supporting closer to 40-50 pairs as some birds are known to have failed on third broods. 

I am currently on the look out for signs of these 355 birds. I know mortality rates are high for young; several cats will have removed some and I have seen at least two Sparrowhawks recently. I have the notional 60 House Sparrows coming in for food as in previous years and so perhaps there are 6 other flocks of similar size distributed amongst the 29 houses in the village but I haven't come across this number of birds while walking the dog. I saw one small flock on a 'fly out' from the village only for them to turn around at a distance of some 150m. I am suspecting that I may need to go and visit a couple of isolated properties away from the village to find a few more answers.


No good blowing the upper breast feathers on a House Sparrow to see the start of moult. This bird has dropped the innermost primary (P1) so is a 3JM. I have not found any sign of the ventral tracks on the body until P3 is starting to appear. Note the paleness on the inner section of the primaries (see end of article).

Sexing of juvenile birds is possible at quite an early age. As the primary moult is progressing the marginal coverts are moulted. This female bird had dropped P4.

 

5 old primaries and this male bird with a moult score of 22 or 23 has replaced GCs, but has yet to complete the lesser coverts and tertials.




Adult females and juvs. can sometimes be a little awkward to determine. Reddish brown tones in the head and a signs of a gape are always useful pointers for juveniles.


This adult female shows some warmer chocolate brown markings in the head and no gape.


In marginal birds, under tail coverts are always worth looking at but House Sparrows will readily mess these feathers. Compare these loose juv. feathers with the bird below. 


The adult female under tail covers have more structure and as in this bird end abrasion can be seen clearly. Some adult female birds will have little of these feather remaining. 


If the under tail coverts cant be used, the upper tail covers will usually show fretted ends to a structured feather as in this adult female.


This juv. female has a moult score of 23, P6 has dropped and the secondary moult has begun. Towards the end of moult, many House Sparrows can still be aged by looking at the weak structure and colour of any remaining inner most secondaries.


This juvenile was quite different from other birds. It is quite usual to see poorly pigmented wing feathers in juveniles but this is quite extreme and also appears in the tail. My observations suggested that this bird was not part of any flock and was often feeding and flying around by itself. 3JM, moult score 1.

The moult detail recorded in the juveniel birds handled in 'my little part of' Carmarthenshire followed that detailed in Ginn and Melville - Moult in Birds ISBN 0903793024.

Tuesday, 4 August 2020

Summer news

At this time of year a lot of attention is given to the three main reed bed species breeding on the Teifi Marshes; Reed Warblers, Sedge Warblers and Reed Buntings.


Looking at data so far this breeding season (from 1st April) it appears that generally numbers are looking good despite the late start due to Covid 19 restrictions.

Reed Warblers --   31 RAS adult re-encounters. This compares well with RAS birds last year which were 35 by this date. Oldest was ringed in July 2014.  38 new adults ringed. Juvs increasing with 62 so far. This is slightly up on the same dates last year when 40 new adults and 41 juveniles had been ringed.

Reed Buntings --   22 RAS adult re-encounters , compared to 28 last year. 38 new adults and 23 juveniles compare with 12 new adults and 44 juveniles last year.

Sedge Warblers -- Though not one of our  RAS study species but 14 birds have been re-encountered that were ringed in previous years. Oldest was ringed in August 2015

As mentioned in the last blog it been a good month for Kingfishers being easy to see on the Teifi Marsh with a maximum of 6 at one time on Kingfisher pond. 10 have been ringed.
Many excellent photos have been shared on the Welsh Wildlife Centres Facebook page. Worth a look at this selection by Tommy Evans
Teifi Marsh Kingfishers 
And this by one of our trainees Toni Henwood, whose photography skills are already being put to good use with colour ring sightings!


A quick look at Willow Warblers recorded this season so far -  Teifi Marsh and Blaenduad 36 new.  Not a direct comparison but last year by this time 299 had been ringed. The biggest change is due to the loss of habitat in good net locations following the widespread fire at Blaenduad. One Willow Warbler caught at Mallard pond in June had been ringed there the previous May.

Our House Sparrow total has shown a big increase in previous years due mainly to increased garden ringing during lockdown and the start of a possible RAS study which may use colour rings. Last year 87 new, 25 adults and 31 juveniles. This year 513 new, 155 adults, 334 juveniles and the rest pulli in nest boxes.

We were unable to ring  Storm Petrels at Mwnt in June this year as it was closed but we managed a couple of very quiet visits in July. A Stormie night is always special even if not many Petrels especially with the added interest of Comet Neowise this year and Manx Shearwaters calling overhead.

Comet Neowise over Mwnt  (Dyfed James)

A recovery recently received from the BTO involved the same bird which shows typical movements of a non breeding bird around the Irish Sea.

Storm Petrel  2674680
Ringed by us at Mwnt, Ceredigion 17/07/2017
Subsequently encountered on the Llyn Peninsula, Wooltack Point by Pembs Ringing Group then just 11 days later on Bardsey Island

Porth Iago, Gwynedd     06/08/2018 385 days, 78km N
Wooltack Point, Pembs 11/07/2020 1090 days, 62km SW
Bardsey Island                19/07/2020 1098 days 72km N


Another recovery received this week was a Goldfinch ABE2665
Ringed Boncath, Pembrokeshire 10/07/2019
Found dead after hitting a window 13/03/2020 in Saubusse,Landes, France
247 days 165 deg SSE


Goldfinch movements are very variable but this one could be an example of the population that breed here and spend winter in the warm further south.

As usual for late July and into August, Hirundine numbers are increasing coming to roost in the Teifi Marsh at dusk. We have had a few sessions ringing mainly Swallows but also some Sand Martins, Pied Wagtails and a House Martin, only the 8th ringed by the group.

Juvenile Pied Wagtail

More sunset evenings like this to enjoy at Mallard Pond over the coming weeks of migration monitoring.



(Wendy J and Rich D)