2018 Hawfinch Survey Update

2018 Hawfinch Survey Update

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By Marcus Ward 16 January 2019

Overview

Bait stations were established at three locations with two at Bolderwood and the third at a new site at Fritham that was established early in the season.  The Bolderwood area remained the core study site, however Fritham was productive with good numbers of Hawfinch visiting the bait, in total 70 new Hawfinch were colour-ringed by three ringers (Marcus Ward, Nigel Jones & Kevin Sayer) and 495 re-sightings were recorded via the trail cameras. In addition, six new roosts were located bringing the known total to 36 in the New Forest and two in the Test Valley.

2018 Fieldwork

Two bait stations were established in the Bolderwood area that were operational from January. An earlier start than previous years in the hope that we could attract some Hawfinch that were part of the large invasion of the species that was experienced across the UK over the winter of 2017/18. A new bait station was also established in early May on Fritham Plain in an area where breeding Hawfinch have been recorded in previous years.

A total of five birds were caught at Bolderwood in Feb and March with just one possible migrant caught on 5th March, a notably heavier and larger individual when compared with other birds caught in the area suggesting that it could be from a migrant population. In total 50 Hawfinch were caught and colour-ringed at Bolderwood and 21 caught and colour-ringed at Fritham, in addition 495 re-sightings were recorded via the trail cameras, the majority of these coming from the Bolderwood area.

Of note, very little movement was recorded between the two bait stations despite being located just 400m apart. Both bait stations had regular visitors taking food on a near daily basis but only two individuals (adult male AN & adult male CX) were recorded visiting both bait stations with any regularity.

Several breeding pairs of colour-ringed birds were confirmed using the trail camera images, of particular interest was adult female AF and adult male AC who successfully bred together for their third successive year. In 2016 and 2017 this pair were frequently recorded together at the bait station in the hollies whereas in 2018 they were recorded daily at the bait station in North Oakley and not at all at the bait station in the hollies. Patterns of paired birds were also picked up at the bait stations, the male and female of paired birds were frequently recorded together at dawn and dusk where the male was often recorded courtship feeding the female, of these recorded pairs the male would continue to visit through the day, but the female was generally just seen at dawn and dusk (more often at dawn).

At least eight territories were mapped across the Bolderwood area though much less time was put into looking for territories in 2018. Breeding success was much improved though compared to 2016 & 2017 with the first fledged juvenile recorded on 14th June, in total five juvenile Hawfinch were ringed across the two locations.

Roosts

As part of my wider Hawfinch studies in the New Forest, six new roosts were found across the New Forest in 2018 bringing the overall total number of known roosts in the Forest to 36. In addition, two roosts were found in the Test Valley at Ampfield Wood and Farley Mount CP. For the seventh consecutive year, two roosts were monitored fortnightly throughout the year at Blackwater Arboretum and Holm Hill Inclosure (table one, below).

Site Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Blackwater 41 52 31 28 12 5 1 4 2 25 14 18
Roost #2 57 66 54 23 18 9 14 18 33 62 45 25

Table 1. Monthly maxima at monitored Hawfinch roosts

Other known roosts are counted at a minimum twice per year, the large number of roosts that have now been mapped makes it difficult to monitor all roosts more regularly though Simon Currie has kindly been covering one roost in the south-west of the Forest through the winter months (in addition to finding a new roost in the north of the Forest).

The roost at Little Holm Hill, Denny Inclosure was clear felled during the winter of 2017/2018, this was previously a significant roost that drew in good numbers of Hawfinch and supported a sizable breeding population in the adjacent areas of mature beech. Through late April and May Denny Wood and Denny Inclosure was surveyed and just one possible breeding territory was found. This area was thought to hold a significant colony of around 20 pairs in previous years, the habitat in the surrounding area has not significantly changed therefore we have to assume that the removal of the roost is the cause of the loss of the breeding colony, highlighting the importance of the roost as a central part of Hawfinch society.

 

Table 2. Summary of monthly max counts at roost #2 over 6 years
         Table 2. Summary of monthly max counts at roost #2 over 6 years

 

Pair bonding Hawfinch at dusk on 6th May, thought to be ad male BT and ad female FA
                  Pair bonding Hawfinch at dusk on 6th May, thought to be ad male BT and ad female FA

 

Ringing Recoveries

A selection of the more interesting recoveries and controls associated with the Bolderwood area:

Hawfinch (adult female ‘AF’ ring no NW83103)

22nd May 2016 – Caught and ringed as an adult female at Bolderwood

18th June 2016 – Confirmed to have successfully bred, paired with adult male Hawfinch ‘AC’

16th June 2017 – Confirmed to have paired with adult male Hawfinch ‘AC’ success unclear

11th June 2018 – Confirmed to have successfully bred, paired with adult male Hawfinch ‘AC’

Paired over three successive seasons with the same adult male

Hawfinch (adult male ‘AK’ ring no NW83017)

11th June 2016 – caught and ringed as an adult male at Bolderwood

2nd June 2018 – Recorded on trail camera at Fritham Plain

Travelled 4.9km in 722 days

Great Spotted Woodpecker (2nd year male, ring no LJ72222)

30th May 2016 – Caught and ringed at Bolderwood Hollies

22nd May 2018 – Re-caught by Tony Davis at Bolderwood Lodge

Travelled 2km in 722 days

Sparrowhawk (1st year male, ring no DT22771)

16th November 2017 – Caught and ringed at Bolderwood Hollies

3rd May 2018 – Found freshly deceased at Acres Down, decapitated, presumed Goshawk kill

Travelled 3km in 168 days

 

 

Adult male DN at the bait station 27th June 2018, first ringed on 13th May 2018
                    Adult male DN at the bait station 27th June 2018, first ringed on 13th May 2018

Future Plans

Funding of just under £6000 has been secured to enable the purchase of 10 GPS/radio tags which we plan to deploy in the Bolderwood area during the 2019 breeding season. The tags will be fitted to adult males and will enable us to track birds in the field via a radio receiver. They will hopefully be retrieved as they will be fitted to birds that are proven to be regular vistors to the bait whereupon we will be able to download data from the GPS portion of the tag. This data will enable us to identify both the nest and roost site locations and help us better understand roost site fidelity, in addition it will enable us to map important feeding areas and show how widely breeding Hawfinch range.

We will also maintain the Bolderwood site as a BTO RAS study site (Ringing Adults for Survival) and continue to bait at Fritham. In addition, I will actively look for a new ringing site on crown land in the south-east of the New Forest. I am also hoping to gain wider access to the Beaulieu Estate to enable me to look for roosts sites and map the breeding range of Hawfinch on the estate.

Acknowedgments

Many thanks to both Andy Page and Andy Shore for their help and support this year. Also thanks are due to my ringing trainer Graham Giddens and fellow ringers Nigel Jones and Kevin Sayer in addition many individuals have supported with fieldwork and here I must mention Simon Currie who has both monitored and found roosts. I am also grateful funding and support received from RSPB, BTO, HOS, Barker Mill Foundation, Lush Cosmetics, Ornitholidays and Paul Matthews at Nutbags.

 

Marcus Ward

December 2018

Second year male DS at the bait station 19th May 2018, first ringed on 16th May 2018
                          Second year male DS at the bait station 19th May 2018, first ringed on 16th May 2018