Guidelines for the Selection of Biological Heritage Sites

Contents

7. Section 2: Species Guidelines

7.6 REPTILES AND AMPHIBIANS

i) REPTILES

Re1 Any site which regularly supports a population of any species of native reptile other than common lizard.

Application

The guideline covers the following species in Lancashire:

Vipera berus	Adder
Natrix helvetica	Grass Snake
Anguis fragilis	Slow Worm

Site boundaries should take account of habitat area utilised by these species at all times of year where these contribute to the essential requirement of the species e.g. hibernating habitats. Populations which are the result of deliberate introductions are not eligible, except where they form part of a recognised species recovery programme.

Justification

With the exception of the common lizard, all native species of reptile are believed to be rare or absent in Lancashire, populations of species present having declined to very low levels over a long period of time.

ii) AMPHIBIANS

Application (all amphibian guidelines)

These are the only species guidelines (with the exception of Guideline Bi6) which are based on quantitative counts of individuals at a site. They are based closely on the corresponding guidelines for the selection of biological SSSIs (NCC 1989). Counts should be carried out only by adequately experienced amphibian surveyors.

Eligible sites should be limited to those which support self-sustaining populations: garden ponds or other sites into which amphibians have been introduced and are sustained only by direct human intervention should be excluded.

Boundaries for amphibian sites should reflect the needs of these animals in both their aquatic and terrestrial phases. They should, where appropriate, include adjacent terrestrial habitat known or likely to be used by newts in particular, including hibernating sites. An amphibian site may contain more than one body of water. To determine the population size of a site where several ponds are utilised by amphibians, counts for each species are summed from all of the ponds within 250m of another pond in the same cluster, and not separated by any obvious barriers to dispersal. Other ponds within 500m of this core area may be important to the long-term viability of the site, as they can be considered to constitute part of the same metapopulation, and may, therefore, be considered for inclusion.

The numbers of amphibians returning to breeding ponds may fluctuate considerably from year to year. To overcome this, and achieve a more accurate estimation of population sizes and stability, counts made during the breeding season should be available for each species for at least 3 years. These counts should be averaged, the averages then scored as instructed below, and consideration for designation as a Biological Heritage Site based on the final score. Where counts are available for less than 3 years, sites which achieve the qualifying scores may be included as provisional entries.

Justification (all amphibian guidelines)

All amphibian species are believed to have declined significantly over Britain in recent years, largely as a result of habitat loss and pollution. Lancashire remains an important county for amphibians, and the protection of the best breeding sites and associated terrestrial habitat is justified for all species.

Am1a Any site which regularly supports a good or "exceptional" population of great crested newt.

Application

The terms "low", "good" and "exceptional" are defined in Table 7, reproduced from NCC (1989). The scoring system shown in Table 7 has been further developed by Grayson et al. (1991) by including an evaluation of the number of eggs present in the breeding season, and by scoring ponds that occur in clusters more highly than those which are isolated. Thus, any site may be considered for inclusion under this guideline if it supports a population of great crested newt (Triturus cristatus) characterised as follows:

five or more adults observed or netted in day time; or
ten or more adults counted by torchlight at night; or
ten or more adults caught in bottle traps; or
eggs estimated at many 100s; or
newts breeding in four or more ponds in a cluster.

Justification

The great crested newt is a species which is vulnerable in Europe and, considered to be a species of Community interest in need of strict protection. As a consequence it is afforded special protection under the Wildlife and Countryside Act 1981 (as amended) and the EC Habitats Directive.

Field work by Grayson and others in north west England (Grayson et al. 1991) has shown that egg search techniques can provide an estimation of the relative size of populations of great crested newt, whose eggs are easily distinguished in the field from those of other newts. Such studies have also indicated the importance of pond clusters in ensuring the survival of great crested newt populations over a number of years.

Am1b Any site which regularly supports a population of natterjack toad.

Application

The natterjack toad (Bufo calamita) is now believed to be extinct in the administrative county of Lancashire. Any site which in future satisfies this guideline, including those supporting planned re-introductions of this species, will be considered for inclusion.

Justification

Natterjack toad receives special protection under the Wildlife and Countryside Act 1981 (as amended), being a rare species in Britain.

Am2 Any site which regularly supports an exceptional population of any amphibian species.

Application

This guideline applies to all sites (including relevant terrestrial habitats), which support "exceptional" populations of amphibians (not included in Guideline Am1a or Am1b), as defined in Table 7.

Justification

See all amphibian guidelines.

Am3a Any site which regularly supports five species of amphibians.

Application

All sites regularly supporting all three newts, common frog and common toad should be selected.

Justification

Sites supporting all three newt species, common frog and common toad are uncommon nationally, being restricted to those geographical areas where the ranges of all the species coincide.

Am3b Any site with an amphibian species assemblage score of 7 or more.

Application

The scoring system follows NCC (1989), reproduced as Table 7.

Scores must be for breeding sites observed during the breeding season. Daytime netting should be made during a 15-minute period for sites with less than 50m of waters edge, for 30 minutes for sites with 50-100m, etc. To compute the total score for a site, add the scores for individual species and add one point for four of these species present and two points for five species.

Table 7 A scoring system for the selection of sites with assemblages of amphibians (From NCC 1989).
(See Guidelines Am3b)

Amphibians		"Low" Population Score 1	"Good" Population Score2	" Exceptional" Population Score 3
Great Crested Newt	Seen or netted in day Counted at night	<5 <10	5-50 10-100	>50 >100
Smooth Newt	Netted in day) Counted at night )	<10	10-100	>100
Palmate Newt	Netted in day) Counted at night)	<10	10-100	>100
Common Toad	Estimated Counted	<500 <100	500-5,000 100-1,000	>5,000 >1,000
Common Frog	Spawn clumps counted	<50	50-500	>500