Tag: Mammals

North Merseyside Biodiversity Action Plan
Red Squirrel Sciurus vulgaris

1 Current status
1.1 National

Once ubiquitous in Britain, the Red Squirrel has undergone a drastic decline during the last 100 years. Following the introduction of North American Grey Squirrels in the nineteenth century, Red Squirrels have been lost from most of southern and central England. They are now essentially restricted to parts of Scotland and the north of England with small isolated populations elsewhere. There is no sign that their rate of decline is slowing.

Squirrel pox virus carried by Grey Squirrels is now proven to be the main threat to the Red Squirrel’s survival.

1.2 Local
In North Merseyside the Red Squirrel remains relatively widespread. The key stronghold is in Sefton where the coastal woodlands support higher than average population levels. The population extends into the urban areas of Southport, Formby, Crosby and Blundellsands. Regular monitoring of the Sefton Coast Woodlands Red Squirrel population has shown a relatively stable population of around 800 – 1200 animals. Population estimates are worked out using ‘distance’ techniques and represent minimum numbers. Natural fluctuations occur in any small mammal population due to variations in over-wintering and breeding success.

This number is further boosted by an estimated population of around 600 animals in the urban areas and Buffer Zone Woodlands, Recent losses have occurred in both the Sefton Coast Woodlands and Buffer Zone due to squirrel pox.

There are small numbers in Knowsley and St. Helens. Surrounding populations in West Lancashire are under severe threat and some have become extinct.

When faced with competition from Grey Squirrels, Red Squirrels have been shown to compete for longer in conifer forests with a mix of tree species and a diverse age structure of trees to ensure continuity of food. The presence of large-seeded broadleaved trees (oak, chestnuts, beech and hazel) aids Grey Squirrel colonisation and threatens Reds.

North Merseyside Biodiversity Action Plan
Water Vole Arvicola terrestris

1 Current status
1.1 National

The water vole is found throughout Britain but is confined mainly to lowland areas near water. Once common and widespread, it has suffered a severe decline in both numbers and distribution. A national survey in 1996-98 estimated an 89% loss since 1939, with a projected 94% loss by 2000.

The British population is estimated to have declined by 88% over the seven year period between the two national surveys of 1989-90 and 1996-98.
The Water Vole is a Priority Species in the UK BAP because of its declining population.

1.2 Local
The national survey of 1989-90 located water voles at 75% of Merseyside sites. A 1999-2000 survey found water voles present in 53% of all suitable North Merseyside locations. Liverpool has little suitable habitat for water voles, whereas 75% of sites in St Helens were positive. In Knowsley, Sefton and St. Helens water voles are relatively common on canals, rivers, brooks and ditches. It appears that North Merseyside, together with neighbouring areas, remains a stronghold for water voles. If they are declining locally, it is almost certainly at a much slower rate than nationally.

North Merseyside Biodiversity Action Plan
Bats (Pipistrelle Pipistrellus pipistrellus/pygmaeus, Brown Longeared
Plecotus auritus, Whiskered/Brandt’s Myotis mystacinus/brandtii,
Natterer’s Myotis nattereri, Daubenton’s Myotis daubentonii, Noctule
Nyctalus noctula)

1 Current status
1.1 National
All seventeen species of bat resident in the UK are in decline. The most common, the Pipistrelle suffered population losses of up to 70% between 1978 and 1993 but it remains widespread with an estimated UK pre-breeding population of 2 million. Common Pipistrelle (Pipistrelle pipistrellus) is no longer a UK BAP Priority Species since its population is thought to be stable in the UK. Brown long-eared, Soprano Pipistrelle (Pipistrellus pygmaeus) and Noctule are UK BAP Priority Species due to a decline in numbers.

1.2 Local
Pipistrelles are widely distributed throughout North Merseyside, occurring in all four districts, and are the species most people come into contact with – they are the species most often found roosting in buildings and feeding in urban areas. Brown Long-eared and Noctule Bats are less common but are also found throughout North Merseyside. Daubenton’s Bats feed almost exclusively over water.

Therefore their distribution is localised and has been recorded from Sefton, Liverpool and St Helens. Whiskered/Brandt’s and Natterer’s Bats are rare locally. Whiskered has been located in Sefton and St Helens and Natterer’s only in St. Helens so far.

No information exists about the size of or changes in local populations but it is believed these mirror national trends. A survey and monitoring scheme (Liver Bats)was initiated in north Merseyside in 2007 to try to gauge the size and status of local populations.