Titchfield Haven Ringing Update - August 2016

I have recently had a few enquiries from birders asking how things have been going with the ringing at Titchfield Haven this year so I thought it was time for a blog update. Subscribers to Birdguides or Rare Bird Alert will no doubt have seen the images of the Aquatic Warbler that we ringed back on 13th August, and that has unquestionably been the highlight of our season to date. This individual was the 17th to be ringed at the Haven and the first since 2009, so it was long overdue. It is great to see a few others turning up on the south coast so you never know, we may even get another, let's hope so.

Juvenile Aquatic Warbler - Titchfield Haven August 2016

Juvenile Aquatic Warbler  - Titchfield Haven 2016

Our ringing totals this year for most species have been disappointing and as I write this post there have only been three mornings where we have caught more that 100 birds. This morning (2nd September) we did catch nearly 150 but the totals in the graph and table below only cover to the end of August, so I will post about that on another day. Typically we would be expecting to catch between 150 - 250 birds at this time of year, but the distinct lack of migrants passing through or over our ringing area has been alarming. The figures for the usual selection of species (below) covering 2010 - 2016 show the total for this year as being the second lowest. When you consider that for 2010 - 2015 the totals are to the 23rd August, whereas the 2016 total is to the 31st August, it is likely to be the second lowest by some way.

Selected species ringing totals 2010 - 2016

Selected species ringing totals 2010 - 2016

You can see from the figures that all of the species totals we have selected are below average as is the grand total, which includes all birds ringed. Interestingly though I have been catching excellent numbers of Goldfinch and Greenfinch in my garden, and the totals to date have already surpassed my best ever annual totals for those two species. We have been discussing the possible reasons for totals being so low and can only really conclude that poor weather during May and June may have reduced breeding success for migrant species, but that is just our opinion.

As yet we have been catching very few adult birds, therefore it is possible that many species are still breeding so there is still the chance that some species totals will pick up, but for Willow Warbler we are pretty much done and dusted, so it is looking like a dismal year for this species.

Bird Ringing Summary, Titchfield Haven - October 2014

With the autumn migration season at the Haven gradually drawing to a close, and the first Redwings and Bramblings of the autumn returning, I have been playing around with some of the species ringing totals. But rather than just focus on the last five years, I have looked back to 1998 at a selection of species. As well as looking at the capture totals between 1998 and 2014, it has also allowed me to look at the general trend of each species over that period. Initially I have looked at those species that we are unlikely to catch again this year but as the season progresses I will add other species. The table below provides information on a selection of passerines, including those that are regular and others that are more uncommon.

The table above looks at the ringing totals between 1998 and 2014 for a selection of passerines.
The totals in red are record years, the total figure is the total number of birds ringed in that year,
not just the total of the species shown.

As I have stated previously the total of 270 birds for Willow Warbler was a record for the site by a good number, as illustrated above. Between 1998 and 2014 the previous highest total was 158, and we have come close to catching 150 birds on three other occasions. Looking at the trend for the last 16 years there is a steady increase. It is difficult to interpret what this means but certainly the number of birds being caught each year is showing a gradual increase.

The Grasshopper Warbler total ended with a total of 340 birds, which is the fifth highest total ever for the species. Once again there is a strong upward trend for the species but that is likely to be slightly skewed by the amazing total of 950 birds in 2011.

The total of 151 Common Whitethroats is the second highest total for the species and once again the trend for the capture totals is a strong upward one. Looking at the totals it is evident that three of the last four years have produced the first, second and third highest totals which could suggest that the species has been having productive breeding seasons recently.

Another species showing a strong upward trend is Garden Warbler and this year's total of 67 was the third highest ever. It is interesting to note just how few birds are ringed annually, in comparison to other species such as Common Whitethroat and Blackcap. Could this indicate the smaller numbers of birds that breed in the British Isles or do Garden Warblers not migrate through the Haven in high numbers?

A species that we get asked about every year when we carry out public ringing events is the Aquatic Warbler. It is a species that is on most Hampshire birders wish list and a species that I have been fortunate to get to grips with on many occasions. Since 1972 only 16 Aquatic Warblers have been ringed at the Haven; the first was in 1977 but 15 have been between 1998 and 2009. We have had several years with multiple captures with the peak being 2006 when four birds were ringed.

Aquatic Warbler - Titchfield Haven 2009

Since 2009 we have not caught an Aquatic Warbler at Titchfield Haven and subsequently there is a strong downward trend for the species at the Haven. Aquatic Warbler is classified as Vulnerable and has declined rapidly in previous years due to the destruction of its habitat. Its decline has been stopped in some areas due to intensive management but in countries like Hungary the species has been quoted as declining to extinction. The decline in the species may be reflected in the lack of birds being caught at the Haven in recent years.