Tuesday 23 May 2023

The resilience of the Spa Bridge Kittiwakes!

 Earlier this year the news of gull proofing of Scarborough Spa Bridge by North Yorkshire County Council (NYCC) to evict 270 pairs of a UK Red Listed species was a shock to many all round the country. Kittiwakes have been in decline for some years in the UK, so much so that they are a species of conservation concern. Although there are signs of some levelling out of the population in localised areas of the UK after a steep decline, some of the Yorkshire colonies are showing alarming breeding results. 

Spa Bridge can be classed as an "A" listed colony, a "good" colony. Studies of breeding productivity there show it to be of significant importance, averaging over one chick per nest. Some local study plots are only half that, and in some cases total breeding failures in recent years.

So how have the Kittiwakes reacted to the 2500 "fire gel" tubs. The first to return to inspect the bridge on 17th March were observed to panic as they got close to the ledges, they quickly flew back to rest on the sea in South Bay where they formed a small flock. The birds were so desperate to get back onto the ledges that where the odd gel tub had fallen off, maybe due to the weather (?), by late March some individuals started to settle for short periods. By early April up to 30 were on ledges, in gaps where more gel tubs had fallen. Many were settling on the girders on the bridge, or loafing on the roofs of local businesses, I bet the owners were pleased with the NYCC actions!

More Kittiwake were arriving throughout April, and to our surprise, they seemed to get used to the tubs, more and more birds landing close to the tubs. After all this was a five star hotel, why settle for any less? 

Early May saw nestbuilding! A closer inspection showed a significant number of gel tubs missing. Could this be assisted by Kittiwakes? Perhaps the glue had failed on the sandstone? A count on 9th May revealed a total of 101 part constructed nests, over 200 birds around the bridge. The latest from the bridge is that 97 birds are seemingly incubating eggs, and still lots of construction of nests taking place.

This is an astonishing result, the Kittiwakes showing tremendous resilience and persistence to succeed. Not what was expected!

So what for the future of Kittiwakes on Spa Bridge? That's in the hands of NYCC.

RSPB, recognising the importance of chick productivity on the bridge, are hoping links can be made with NYCC to help manage gulls in Scarborough and along the coast. The Yorkshire Coast Urban Gull Partnership has been set up with attendees from key conservation bodies, RSPCA, North Yorkshire Police Wildlife Crime Officer, and local experts who study the colonies. Hopefully everyone can work together for the mutual benefit of the Kittiwakes and local businesses.

One of the central columns, many gel tubs still present on the top ledge.

Nests at all stages of construction. This one is quite a structure having started from scratch last month.

Construction in progress.

A Kittiwake "lawn". Constant collection of grass for nests produces shorter patches of grass near colonies. They've not heard of "No mow May"!!

Resilient in their pursuit for prime positions! Many now sat above/next to gel tubs, however a closer inspection of this tubs shows help from the bridge breeding pigeons above.

Not all birds present on the ledges are of breeding condition. Kittiwakes normally start breeding at around four years old. This two year old can be aged with extra black in the outer wing.

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