Halton Skylark Report 2007 Contents Introduction 3 Methodology 5

Halton Skylark Report 2007 Contents Introduction 3 Methodology 5 Results 7 Analysis 8 Conclusion 10 Appendices; I 12 II 13 2 Introduction The Skylark Alauda arvensis has traditionally been held in the popular imagination by the people of Britain. It has one of the widest ranges of any bird in the UK and could once be seen on any patch of open land, from coastal saltmarshes to moorland and in arable fields up and down the Country. Although the bird is non-descript brown, it can be easily recognised by its distinctive call and flight pattern. In the early spring, males can be seen taking off vertically from the ground and soaring to height of up to 100m. The song it lets forth is a loud, distinct chirrup, often described as sounding ‘liquid’, and will be continued for several minutes as the bird hovers high above it’s territory. Sometimes phrases mimicked from other birds can be heard within the song. This behaviour is used by male birds in order to establish territories for the coming breeding season, which lasts throughout the summer and may produce up to four broods. At first sight, the Skylark is an unexciting brown and grey streaked bird with a buff belly. Its most distinctive feature is the crest on its head which the males are able to erect, although the crest is often pushed flat by windy conditions. The wings are pointed at the tip and flap rapidly as the bird takes off and propels itself vertically. The overall length of a skylark is 16-18 cm, making it a similar size to a swallow (but lacking the long tail). Figure 1, a Skylark © Jeff Clarke The British population of skylarks is predominately resident all year round, although some breeding grounds in Scotland are vacated in the winter. Come autumn, flocks of skylark can often be seen congregating on stubble fields, their numbers swelled by over wintering northern European birds. Skylarks will not be found near established trees and large bushes, and so are restricted to very open land, which is why they are found in places like arable fields and saltmarsh. Once the spring is warm enough to commence breeding, a nest is formed from a hollow on the ground and lined with leaves. The female will usually lay a clutch of three to four eggs (although this number can vary from one to six), and only she will incubate them. When hatched (after about two weeks incubation) the 3 chicks will be fed by both parent birds on insects at first, but after a week, a variety of plant matter will be introduced into the diet. By twenty five days, the juveniles will have become fully independent. Further broods in the same year will be raised in the same breeding territory. The ideal breeding habitat for skylarks is open countryside with vegetation cover of about 20-25cm in height, and which will provide plenty of seeds and other vegetable food (such as shoots) throughout the summer. In this type of habitat, skylarks are able to raise two to three broods during the breeding season, which is the minimum number needed to sustain the population (RSPB). During the last quarter of the twentieth century the population of skylarks in Britain has declined so much that it is listed as a Red Species (species of most conservation concern) by the ornithological organisations of the United Kingdom. Elsewhere in Europe there have been declines too, and the bird is a European species of concern, although the global population as a whole is not thought to be under threat. The decline in numbers is thought to be linked to a reduction in the ideal breeding habitat, which has reduced both breeding density (per ha of habitat) and the number of successful broods by each pair per year. Data produced by the Royal Society for the Protection of Birds (RSPB) and British Trust for Ornithology (BTO) suggest that there has been a steep decline in British population of Skylarks since the 1970s. The RSPB suggests that this is as much as 75% of the population between 1972 and 1996. BTO statistics show that during and since the 1990s the decline has continued, but at a slower rate. This trend is similar to that of many farmland birds and researchers associate it with changes in farming practices. One of the main factors causing decline is thought to be a switch from spring-sown cereal crops to autumn/winter-sown cereal crops. The basic reason why this is thought to be a problem is that during the summer breeding months, winter-sown cereals will have grown too tall and dense for skylarks to nest in. Many birds may then attempt to nest in the tractor-tracks running across the field, resulting in greater mortality when farm machinery is in operation. Also, cultivation of autumn/winter- sown crops does not leave stubble during the following autumn, which is in important food source for skylarks. Other factors associated with agricultural intensification include greater use of herb and pesticides which remove weed seeds and invertebrate food sources. Many farms now also produce more silage, rather than hay, to feed livestock on which is not advantageous for skylarks because it will be cut before the end of the breeding season, or at least before the skylarks have had chance to reproduce enough times to support the population. Such a sharp decline in the number of birds has lead to the skylark becoming a Biodiversity Action Plan species (BAP species) for the United Kingdom. Within the BAP process are local BAPs (LBAPs) which used to remedy the losses for locally sensitive species. In the Cheshire region, farmland birds as a whole, and the skylark in particular have become LBAP species. As a result, Halton Borough Council have included the skylark in its own list of LBAP species. Within the Borough of Halton, there are a number of habitat areas where skylarks are known to exist. Halton has a high proportion of land dedicated to housing and 4 industry, habitat types which the BTO cite as being of low value for skylarks (towns have lowest relative skylark frequency out of thirteen habitat types). However, Halton also has areas of farmland, including arable farmland, a habitat which has a relatively high frequency of skylarks. A figure on the amount of farmland will be available on completion of a Phase One Habitat survey, the results of which are due in 2008. Other significant habitats in Halton which can accommodate skylarks include grass and parkland, and the estuarine saltmarsh. The Halton skylark BAP outlines specific targets and measures aimed at conserving the skylark population in Halton. The key target is a 20% increase in breeding pairs by 2015. In order to complete this task, the Borough is currently taking a number of actions (e.g. promoting countryside stewardship schemes to local farmers) which will provide more areas of suitable habitat for skylarks. As well as these practical conservation and habitat creation processes, a system of recording and monitoring is also provided for under the BAP. All existing records for the species in Halton (and the rest of the Cheshire region) are continuously being aggregated on the r ECO rd database, but r ECO rd itself has been commissioned to undertake a programme of skylark recording for 2007. The r ECO rd scheme has targeted specific areas in an attempt to quantify breeding areas for skylarks in Halton. This is to be combined with a data search of the r ECO rd database and analysis of the results forms the Halton 2007 skylark report. Methodology The r ECO rd database was searched in order to map the distribution of skylark records held for Halton. In addition to this desktop study, areas within in the Borough were identified for survey work. These areas were known to support skylarks already, but further data collection was required in order to produce an estimate of the number of breeding territories for each area. The areas that were chosen for study were of differing habitat types and were managed in different ways. Table 1 outlines the areas selected for study. Table 1. Areas selected for skylark surveying Location name Description Habitat type(s) Fields by Hale Lighthouse, An area of agricultural Arable fields of cereal Hale, near Widnes. land under high level crop (to the east) and rape stewardship, flanked to the (to the west) north by Hale Village and to the south by the Mersey estuary. Immediately east and west are more agricultural fields of various types and areas of marsh. Astmoor Saltmarsh An area of saltmarsh to Saltmarsh south of the Mersey estuary, which undergoes little or no management. It is sometimes inundated by the estuary during 5 particularly high tides. Keckwick / Sandymoor An area, predominantly of Grassland, woodland, area farmland and open pasture and arable. grassland. The area as a whole is bounded by the estate of Sandymoor and the Daresbury Science Park. The area is over 1.5km (1mile) west-east diameter and includes land earmarked for development and Keckwick Balancing Lake. Fields around Preston-on- An area comprised of Young plantation the-Hill, Summer Lane farmland only, apart from woodland (maximum tree Wood. an area of young height, approximately plantation woodland. A 1.5m) preliminary survey over the whole area produced only one recording of skylarks, near the plantation woodland (Summer Lane Wood), and hence only this site was selected for further study. For a map of these areas in relation to the rest of the Borough of Halton, see appendix I.

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