2022 was another busy year working with Hawfinch in the New Forest, our 12th year of intensive fieldwork with the species. This short blog covers some of the highlights from a year in the field with Hawfinch.
Roosts
Roost work carried on through the year with two roosts monitored monthly through the year, we now have a decade of data from the two core roost sites. Four new roosts were pinned down through the course of 2022, bringing the overall total of known communal roosts in the New Forest to 50 with a further two in the Test Valley.
Going forward, in addition to the two core roosts that are counted monthly, roosts will be counted through late Feb through to late April in a cycle to ensure each roost is monitored at least once every three years to confirm that it is active and to assess the size of the roost.
I am sure there will always be new roosts to find but we are getting close to accounting for most obvious Hawfinch congregations.
Hawfinch gathering post roost
Breeding
Three nests were found in our main study area and subsequently monitored, including one nest found at an early stage by Andrew Colenutt in a Holly at Bolderwood. The male was found while still lining the nest with moss and lichen, an activity that is rarely observed with Hawfinch. This nest was monitored daily throughout the period on a rota by the team, sadly the nest failed after just weeks. The perpetrator was suspected to be avian, most likely a Jay that was later observed taking Blackcap chicks close-by.
Overall, 13 nesting attempts were recorded, very much the tip of the iceberg for this challenging species. Productivity was good with good counts of juveniles from both communal post breeding nurseries and communal roosts.
Hawfinch gathering lichen to line the nest (Rob Farnworth)
Ringing
Overall, 50 new Hawfinch were colour-ringed, with 185 re-sightings of 50 individuals recorded via the trail cameras. Ringing ceased early after a Chaffinch with suspected Trichomoniases was recorded on the trail camera, we felt the risk of cross contamination to other finch species was too high to continue. Some of the more interesting re-sightings below:
NP04912 (NJ) ringed as a second-year male in the north of the New Forest on 07/03/20.
Recorded at the same location 12/01/22 – 0km travelled in 677 days.
NW83154 (FJ) ringed as a juvenile male at our main study site in the centre of the New Forest 11/06/2017.
Recorded at a location in the north of the New Forest 19/04/22 – 7km travelled in 1773 days.
We get very few re-sightings of juvenile Hawfinch suggesting dispersal from natal area, supported by this recovery.
NV82764 (SI) ringed as an adult male at our main study site 25/06/2015.
Recorded at the main study site 29/05/2022 – 0km travelled in 2531 days.
This individual is also frequently recorded annually at our main study site, often on multiple occasions and was thought to be breeding close-by in an area of plantation Oak.
The re-sightings show that Hawfinch appear to be very site faithful. We have now ringed 305 Hawfinch in the New Forest and have few very records of movements outside of the GPS/Radio tracking, suggesting that our resident Hawfinch are sedentary. However, it seems likely that juvenile birds disperse due to the lack of subsequent records.
Adult male Hawfinch
Late year activity
A poor Beech, Hornbeam and Holly crop in the late year ensured that many Hawfinch appeared to leave the Forest to forage in the wider countryside. All roosts produced considerably lower than average numbers. This was further supported by a notable increase in numbers in Test Valley and surrounding area.
2023 fieldwork
As with previous years the BTO RAS study (Ringing Adults for Survival) will continue at our main study site. In addition, we have established two other data collection locations, working with RSPB Franchises Lodge and local ringer Kevin Sayer. This year we will also be working together with RSPB, supporting a student from Lincoln University researching trichomoniasis in finches. Roost monitoring will also continue, including monthly year-round monitoring of the two core roost site. As with 2023 we will run the Hawfinch fieldwork alongside the ongoing Siskin RAS.
Acknowledgments
Many thanks to Andy Page, Andy Shore, and Maarten Ledeboer (Forestry England) for their help and support and the New Forest Ringing Group team comprising Andrew Colenutt, Helen Schneider, Jamie Ward, Tara & Amy Squire, Saul Alfonso, Rob Farnworth and Georgie Digby who have committed a lot of time to the studies in the New Forest. Thanks also due to Martin Bennett who put in many hours, and Simon Currie who has supported roost monitoring in addition to Nigel Matthews and Roger Webb who’s info helped pin down new roosts. I am also grateful for funding and support received from RSPB, BTO, HOS, Barker Mill Foundation, Lush Cosmetics, Ornitholidays and Paul Matthews at Nutbags.
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