ECOFACT undertake a range of terrestrial macroinvertebrate surveys, both as part of general ecological investigations and also for specific protected and rare species.
Terrestrial invertebrates can be sampled by a range of active collecting methods, including:
- Active and visible species, such as butterflies and bumblebees, may be assessed and identified by direct observation during a walk over survey the site.
- A hand search of important invertebrate habitats, including dead wood, beneath stones, and common invertebrate host-plants, is often undertaken.
- Sweep-netting is a suitable method for flying insects and for sampling vegetation.
- Beating is a method used to dislodged invertebrates from woody debris and vegetation. The dislodged invertebrates are caught on a tray.
- A variety of traps can be used, including pitfall, malaise, flight intercept, sticky and light traps.
- Extraction of insects from leaf litter using extractors or water funnels, is another useful method.
The samples are then preserved and identified in the laboratory following completion of the survey, with taxonomic identification completed in-house with the use of microscopes and keys.
Marsh fritillary Larvae Surveys
Ecofact have recently completed a number of larval surveys for the Marsh FritillaryEuphydras aurinia butterfly; the only Irish insect listed under Annex II of the EU Habitats Directive. The Marsh Fritillary has declined due to changing landuse, but is still widespread in Ireland.
The optimum time to survey for Marsh Fritillary is in the period September and October when the larvae can be found within silken webs on the leaves of its food plant Devil’s-bit Scabious. Our ecologists have extensive experience in both surveys for this species, and also management of the habitats it inhabits.
Whorl Snail Surveys and Management
A total of eight species of Whorl snail are known to occur in Ireland; three of which are listed under Annex II of the EU Habitats Directive. These species are offered protection by the designation of conservation sites which extends the protected status to both the species and the habitats upon which they rely. These species are: Vertigo angustior (EU code 1014), Vertigo geyeri (EU code 1013) and Vertigo moulinsiana (EU code 1016). These species of whorl snails are particularly sensitive to changes in hydrology. Such changes have become more evident in recent times.
ECOFACT have undertaken numerous assessments of whorl snails species and have advised state agencies (including the OPW and the NRA) on the management of these species and their habitats.