Urban Roots Malls Mire Invertebrate Records 2014

Quality Control

We have a very high level of confidence in this dataset. Where necessary, rare specimens were compared against reference collections, those held in the National Museums Scotland collection and identities confirmed with experts.

Method steps

1. A wide variety of sampling methods were used, including: Pitfall traps - Each pitfall trap consisted of a plastic cup dug into the ground so that the lip was flush with the substrate surface. Two small holes were punched through the plastic just below the rim for drainage to prevent loss of catch if flooded by rainwater. Chicken-wire was used to cover traps so as to prevent small vertebrates from becoming trapped, and was attached so as to ensure that it could not be dislodged. A mixture of 70% propylene glycol antifreeze and 30% water was added to a depth of 2.5cm in each trap, and a drop of washing-up liquid was used to break surface tension. Traps were set in four transects of five traps located in different habitats in Malls Mire. Traps were left in situ for two weeks, at which point the catches were collected and transferred to a container and preserved in a 70% isopropanol and 30% water mixture. Traps were reset every two weeks from 23 June to 18 September 2014, totalling seven rounds of trapping. Traps were emptied and reset by Urban Roots volunteers. Bark traps - Bark traps were used to sample invertebrates that live under tree bark. The traps consisted of two layers of plastic bubble wrap, with bubbles facing each other so as to provide artificial bark habitat 40x40cm in size. Dark plastic was used to cover the outside of the trap to prevent light from penetrating the clear plastic, and the trap was wrapped around a tree at 1.5 m height, attached using wire. The traps were left in situ from 9 June to 24 September 2014 (15 weeks) before collection, allowing invertebrates to colonise this new habitat. Invertebrates were collected from the space between the trap and the tree as well as from between the layers of bubble wrap. Specimens were transferred to a container and preserved in a 70% isopropanol and 30% water mixture. A total of 26 bark traps were fitted to trees of varying location, aspect, species and life stage. Bugvac (suction sampling) - A modified leaf blower (Husqvarna 125BVX) was used to suction sample invertebrates from ground level. This has proven the most effective method of establishing the presence of species that live in less accessible micro-habitats such as the base of vegetation, or for small invertebrates which are often under-recorded by more traditional sampling techniques (Wilson et al. 1993). Each sample involved pressing the bugvac nozzle to the ground for 10 seconds at five points. Specimens were then emptied from the net into a white plastic tray, collected with forceps dipped in 70% isopropyl alcohol, and transferred to a plastic collection tube containing 70% isopropyl alcohol. Bugvac samples were collected on 9 June and 23 June 2014. Sweep netting - A 30 cm diameter canvas insect net with a sturdy metal frame was used for sweep netting low vegetation such as grasses or rushes. One sample involved walking slowly forward and conducting 20 sweeps from side to side. Invertebrates trapped within the net were collected using a suction pooter and transferred to a plastic collection tube containing 70% isopropyl alcohol. Sweep netting was carried out on 23 June 2014. Active searches - Various microhabitats were searched by hand. This involved 'grubbing' in the ground layer, overturning stones, and using a range of equipment such as pooters and tuning forks (to lure spiders out onto their webs), amongst other specific techniques as appropriate. Active searches were undertaken on 9 June 2014, with the assistance of children from St. Brigida^??s Primary School. Wherever possible, specimens were identified in the field. Where this was not possible, or where sample methods were obligately fatal specimens were preserved in 70% isopropanol for later identification in the lab with stereo-microscopes as appropriate. Voucher specimens were retained where appropriate. Where necessary, specimens were compared with museum collections to confirm identification. Appropriate references were used in the identification of specimens, and these are cited in the reference list at the end of the report, which can be downloaded from the Publications page at: http://www.caledonianconservation.co.uk/publications/

Malls Mire