Tel: (+44) 01479 870238
enquiries@albaecology.co.uk

Ecological Research

Within this broad field our team provides a wide range of ecological research, both commercial and non-commercial, all in-house. As part of EcIAs or, for example, as part of routine work for designated conservation areas, we carry out ornithological surveys, protected mammal surveys including bat surveys, reptile and amphibian surveys, invertebrate surveys including freshwater pearl mussel surveys, National Vegetation Classification (NVC) surveying, Phase 1 Habitat surveys and specific botanical surveys.

Further specific applications have included, for example, turnover of juvenile Golden Eagles based on DNA studies; reintroduction potential of freshwater pearl mussels to rivers; development of methods for surveying nocturnal mammals; the distribution of rare flowering plants in maritime heath; etc.

We also set aside a proportion of funds each year in order to fund our own non-commercial research, of importance to wildlife conservation, which would otherwise not be funded. This has included work on globally important seabird colonies, hen harrier habitat preferences in Ireland and research into the UK's most important population of the globally threatened freshwater pearl mussel and climate change impacts on this species.

Alba Ecology Research Topics

Forest management and freshwater pearl mussels

A practitioners’ perspective from the north of Scotland

Peter Cosgrove, Neil McInnes, Suzanne Dolby, Derry Gunn, Donald Shields, Cameron Cosgrove and Kenny Kortland
Scottish Forestry cover Spring 2017 From Scottish Forestry Volume 71 No. 1 Spring/Summer 2017 – Figure 1: Surveying a small previously unsurveyed watercourse in Catchment A. Pearl mussels were discovered in this watercourse in 2013.

Most of the world’s remaining globally threatened freshwater pearl mussel populations occur in northern European rivers and streams in partially or wholly forested catchments. As a consequence, sustainable forest management in this area has a pivotal role to play in conserving this species and its aquatic habitat. Using recent experiences from the north of Scotland, we report on how targeted practical forest management has been developed and implemented to aid the protection and recovery of this keystone species.

By considering the unique life-cycle of the freshwater pearl mussel, forest management effort in the north of Scotland has been directed towards:

  1. establishing the baseline conditions (pearl mussel population status) in forested catchments,
  2. blocking forest drainage ditches to reduce forestry derived siltation and runoff,
  3. managing harvesting in such a way as to minimise impacts on the pearl mussel and its host fish,
  4. instream barrier management and
  5. tree restocking/planting.

Breeding Whimbrel habitat characteristics in Shetland

Do Whimbrel adults and chicks use different habitats?

LINKED PAPER

Habitat characteristics of breeding Eurasian Whimbrel Numenius phaeopus on Mainland Shetland, Scotland, UK. Massey, K., Cosgrove, P., Massey, F., Jackson, D. and Chapman, M. 2016. Bird Study. DOI: 10.1080/00063657.2016.1237470.

As part of a study into the potential impacts of a large wind farm proposal on Shetland, a team from Alba Ecology Ltd and Natural Research Projects Ltd collected data on the habitat associations of Eurasian Whimbrel Numenius phaeopus. Shetland is the most important area in the UK for breeding Whimbrel and the Whimbrel population here has declined by around 50% since 1990. Consequently, knowing what breeding Whimbrel require is a prerequisite to effective conservation action.

Figure 1 Whimbrel chick © Digger Jackson
Figure 2 Whimbrel adult habitat with nest in foreground © Digger Jackson

Fourteen study sites on Mainland Shetland (comprising a third of the UK’s breeding Whimbrel) were used to identify three main components of Whimbrel breeding habitats: (i) adult territorial and foraging habitats, (ii) nest site habitats, and (iii) chick feeding habitats. The relationship between these components was investigated using PCA. Habitats used by breeding adults and chicks were significantly different from one another.

Adult habitats comprised of short, heavily grazed blanket bog dominated by Ling Heather, Cross-leaved Heath, Common Cottongrass, Hare’s-tail Cottongrass, Deergrass and Purple Moor-grass with a thick layer of bryophytes but few forbs. The habitat used by adults to nest in was very similar to the general adult habitat (Fig. 2). However, the Whimbrel chick habitats were significantly different in terms of structure from the habitats used by adult Whimbrel. The chicks of Whimbrel, like most waders, are precocial and forage independently of their parents within a few days of hatching. The chick habitats were characterised by small, wet and often linear features within the blanket bog habitat, with plenty of mosses and plants such as Purple Moor-grass and Bulbous Rush (Fig. 4).

Figure 3 Whimbrel nest © Digger Jackson
Figure 4 Whimbrel chick habitat © Kate Massey

The habitat differences between adult feeding/nesting locations and chick foraging locations were very striking and suggest that the presence of both types of habitat may be of importance to Whimbrel on Mainland Shetland. The differences in habitat usage can probably be explained in terms of the chick needs with respect to food, mobility and importantly, cover from aerial predators.

There is now a growing body of evidence (from Lapwings, Vanellus vanellus, to Golden Plover, Pluvialis apricaria) that food availability, vegetation structure and cover from predators may at least partly explain habitat preferences of wader chicks. Habitat structure is important for chicks and the presence of small, wet linear features may be a limiting component on otherwise apparently suitable adult Whimbrel habitats.

References

Massey, K., Cosgrove, P., Massey, F., Jackson, D. and Chapman, M. 2016. Habitat characteristics of breeding Eurasian Article Source: https://www.bou.org.uk/cosgrove-whimbrel-habitat/

Response of incubating Golden and White-tailed Eagles to forest road traffic: results of a pilot study

P. COSGROVE, K. KORTLAND, D. SHIELDS, R. POTTER, J. MURRAY & C. COSGROVE
Golden EagleGolden Eagle © Alba Ecology

Very little work has taken place on the potential impact of vehicle disturbance on breeding Golden Eagles and White-tailed Eagles. Determining whether the routine use of vehicles on forest roads adversely impacts on these two species is important to help inform forest management in Scotland. In 2015–16, a pilot study was undertaken on the national forest estate in mainland Argyll and Lochaber which investigated the impact of routine forest road traffic on 13 incubating Golden Eagles and White-tailed Eagles.

Observations showed that incubating eagles sometimes responded to sound and visual stimuli from passing forest traffic. However, no discernible responses were recorded during 46 vehicles passes (61%), minor discernible responses were recorded during 29 vehicle passes (38%) and moderate discernible responses were only recorded once during vehicle passes (1%). Forest road traffic did not cause incubating eagles to leave or abandon any nests studied during periods of observation.

Detailed analyses were not considered realistic due to the small sample sizes and we recommend that further studies are carried out in Scotland into the effects of vehicle movements on additional pairs of incubating Golden Eagles and White-tailed Eagles.

Tanji River Bird Reserve, The Gambia—a globally important breeding site for Royal Tern Thalasseus maximus

Peter Cosgrove, Paul Doyle, Robin Cosgrove, Roy Goff, Jan Veen and Lamin Manneh
Royal Tern Figure 1. Royal Tern Thalasseus maximus and Caspian Tern Hydroprogne caspia colony, Tanji River Bird Reserve, Gambia, April 2012 (Donald Shields)

Summary.
Tanji River Bird Reserve in The Gambia holds important numbers of breeding seabirds. Monthly monitoring over an eight-year period is reported, together with earlier data. During this time substantial increases of Royal Tern Thalasseus maximus and Caspian Tern Hydroprogne caspia have been recorded. The mean number of nests over the eight years is 21,505 for Royal and 1,688 for Caspian Tern.

Given the mean incubation period of these two species and our monthly survey visits, the number of nests provides an approximate index of the number of pairs, making the Royal Tern colony on Tanji Island the second largest in Africa. Tanji Bird Reserve is thus a globally important breeding site for the species, holding up to 19% of the West African breeding population.

The Bijol Islands and the mouth of the TanjiRiver are the most important sites for gulls and terns in The Gambia and constitute an Important Bird Area (BirdLife International 2011). Foremost amongst these are two islets that lie 2 km offshore (13°23’N 16°48’W) opposite the towns of Brufut and Tanji. In 1993 the Bijol Islands were gazetted and became known as the Tanji River (Karinti) Bird Reserve. The birds of the Bijol Islands were described by Barnett et al. (2001), Veen (2003) and Veen et al. (2003, 2004).

Since then bird monitoring by the Department of Parks and Wildlife Management (DPWM) has been regular and systematic counts of breeding seabirds have been undertaken annually, but surprisingly little has been published on the recent status of breeding seabirds there. This paper reports the systematic monthly counts of breeding seabirds over an eight-year period and focuses on the number of breeding Royal Terns Thalasseus maximus.