Breeding Curlews in Shropshire in 2018, and the SWT / SOS Save our Curlews campaign


Introduction

To complement the BTO’s Bird Atlas 2007-11, Shropshire Ornithological Society (SOS) organized a Breeding Bird Atlas survey 2008-13, with identical methodology to a survey in 1985-90. All 870 of the County’s tetrads (2x2km squares on the OS national grid) were surveyed in each period. The later Atlas did not find Curlew in 62% of the tetrads where it was found less than 25 years previously, and the estimated population declined by 77%, from 700 pairs in 1990 to 160 pairs in 2010.

Population monitoring has also been carried out by several Community Wildlife Groups (CWGs), the earliest since 2004, which has also found a substantial continuing decline, an estimated 20% since 2010. As a result, a Save our Curlews campaign, funded by a joint appeal organized by Shropshire Wildlife Trust (SWT) and Shropshire Ornithological Society (SOS), was launched. This article summarises activities in 2018 (it does not include the results of the “Curlew Country” project, which have been reported separately).

Nest Finding and Protection

This was initiated in two areas, Upper Clun and Clee Hill. In 2017, the respective CWGs estimated a population of 8-9 pairs in the former, and 7-8 in the latter. In 2018 the estimates were 8-9 again in the former, and 7-10 in the latter.

Three nests were found in each area. All were fenced, and no nests were predated, although two eggs were lost from one nest, almost certainly to Carrion Crows.

At one site, two eggs didn’t hatch, and the two chicks that did hatch were deformed, and died very quickly. A post-mortem on these chicks by a vet found signs of retarded bone development due to a rickets-type disease, and possible vitamin B deficiency, attributed to poor nutrition or health of the female at the time of egg laying, and perhaps the low availability of the right kind of food during the hot, dry weather.

At a second site, enclosed by a rabbit-proof fence which had helped successful breeding in previous years, all four chicks starved to death in 2018, as a result of spraying off vegetation (reducing invertebrate food) and very hot weather drying out the ground (again reducing invertebrate food).

Two other eggs didn’t hatch, but the remaining 17 did, and all chicks except one were ringed and radio tagged. Most were lost to predation within 2-3 weeks, but definitely one, probably two, chicks fledged near Clee Hill. Both chicks were colour-ringed. Foxes are shot at the farm where the chick(s) fledged, but it is not known whether this has a significant impact on the local population.

In the Upper Clun, the three chicks whose remains were found had been predated; based on field signs, it is likely that a Buzzard, an unknown avian predator and a fox each accounted for one of the three. The other four were probably predated, but the tags were carried out of range or underground, and not found.

In Clee Hill, one chick definitely fledged and one probably fledged. Four perished in the rabbit-proof enclosure (see above), one was definitely predated by a Buzzard, and two were probably predated, but the tags were carried out of range or underground, and not found.

In both areas, it is likely that the tags were carried underground, as the tags are reliable, and they were searched for extensively. Foxes are therefore the most likely culprit. No chicks were lost to agricultural operations.

Another pair was located at a regularly used site just outside the Clee Hill area. However, Curlew egg shells were found within a tractor rut before the nest could be found. It is not clear if the nest was destroyed by a vehicle, or the egg shell fragment had been moved from the location of the failed nest.

The CWGs have not attempted to find nests in previous years, and the largely upland terrain is difficult to work, so finding and protecting more than a third of the nests in the first year is a good result. Valuable lessons have been learnt for next year.

Other Pairs in These Two Areas

Curlew activity was depressed in April, because of the continuous cold east wind, and some pairs arrived back late, and others may not have got into breeding condition. However, in the Upper Clun, territorial activity was observed at four further nests into mid- or late June, suggesting that eggs hatched, and there was evidence of hatched young at one further site in Clee Hill.

Analysis of winter Timed Tetrad Visits for the Bird Atlas 2007-11 shows that the Upper Clun area has a relatively low density of Pheasants (only one-fifth of that in the Curlew Country area), suggesting that the fox population is also lower there, perhaps accounting for the relatively low level of nest predation. In Clee Hill, there is only one area of high Pheasant density, which is not part of the area where Curlews are found.

Monitoring by Community Wildlife Groups

Three new Community Wildlife Groups were set up at the start of 2018, to plug the gaps to ensure that the vast majority of the County Curlew population is surveyed, bringing the total to 10. These 10 CWGs between them covered 137 of Shropshire’s 870 tetrads, and monitored well over half of the tetrads with evidence of breeding Curlews in the 2008-13 Atlas. Over 270 participants spent over 2,400 hours on these surveys in 2018, very clear evidence of concern in the local community about the decline of Curlews here, and their support for Curlew conservation. This total does not include the time that participants spent in briefing meetings or undergoing training, or the time spent organising the surveys or analysing the results from somewhere around 700 survey maps, or the many individuals submitting casual records.

Together the groups located 85-103 Curlew territories (including about 35 in the area covered by “Curlew Country”), the vast majority of the County population. Two nests were found. At one, the farmer mowed round the nest, but it was predated. The other was fenced, and the eggs hatched.

Other pairs

There is a breeding population of four pairs on Fenn’s / Whixall Moss NNR (three in Wales and one in Shropshire), which is monitored by Natural England. It is believed the pair from Shropshire failed at egg stage, as Corvid-predated egg fragments were found near to the centre of the territory. There are also two pairs on the National Trust’s Long Mynd property, but no evidence of successful breeding. Information is also collected about the location and outcomes of several other isolated pairs.

An estate in the north of the County has fenced a large field regularly used by one pair.

Future Plans

The Appeal is intended to raise funds to continue the nest finding and protection project next year, and extend it to other CWG areas when Curlew territories there have been located sufficiently to give a nest-finder a realistic chance of locating most of them. Between them, the CWGs will continue to monitor the vast majority of the County population, and population trends.

Further Information

The Community Wildlife Groups have a joint website, www.ShropsCWGs.org.uk.

Full details of the SWT/SOS Save our Curlews campaign, including the Strategy, can be found on the SOS website www.shropshirebirds.com/save-our-curlews The full reports of the two Nest Finding and Protection projects can be found on the website.

leo@leosmith.org.uk
October 2019

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