Working Group on Iberian Lucanidae (GTLI)

Justification and objectives
In general, population studies about any species are limited to just one or a few localities and last a few years (Pimm, 1994). Long-term monitoring has a high scientific interest, because it reveals trends and patterns that cannot be detected in the usual short-term studies. Among the animals birds, as usual, are the group for which more information is available (Hildén, 1987; Robbins et al., 1989; Fuller et al., 1995; Siriwardena et al., 1998). Studies about the abundance of invertebrates are much more scarce than those about vertebrates (Taylor, 1986). Species studied have been mainly those with any economic interest. In United Kingdom, Pollard and colleages are working with butterflies. Since 1976 they keep a national network of collaborators (amateurs, rangers from preserves) which monitors the abundance of butterflies (Pollard et al., 1986). This kind of network has been also started in other European countries and since 1994 is working in Catalonia, northeastern Spain (Stefanescu, 2000).

The objective of this project is to monitor the abundance of Lucanus cervus, by coordinating a network in northern Spain, where the species seems to be more abundant. This project would also be easily applicable to Pseudolucanus barbarossa. Specific objectives are similar to those of Pollard:
1) analysis of abundance trends at a large geographic scale, which can be related to general phenomena such as climatic variation,
2) study of the local variations in abundance, due to habitat changes (logging, removal of dead wood, pesticide use, etc.).

Results
Efforts until have focused on finding suitble quantitative sampling methods for the Stag Beetle. We have tried three methods. First, a transect to estimate the abundance of Lucanus cervus (only in Spanish) was adapted from the one utilised by Pollard. Between 1994 and 1999, L. cervus abundance was monitored at El Escañorio (Corvera de Asturias, Asturias, northwestern Spain) using this method. Results are shown in Fig. 4. 4. 1. This project is temporarily discontinued. A similar experience was carried out at Noia (La Coruña, northwestern Spain) during summer 1994, but was not continued.

Second, we tried to find methods of live trapping. In 2002, contact with Deborah Harvey from the UK has provided us with two kinds of live traps (only in Spanish; contact Deborah Harvey for English instructions) which allow to perform population size estimates by mark-recapture procedures (Krebs, 1989). Several methods of beetle marking are now available. In 2005, another suitable trap, the bottle-trap (only in Spanish), was found.

Finally, from some initial trials we developed in 2005 an improved protocol (only in Spanish) to estimate abundance of Lucanus cervus from counts of road casualties.

How to collaborate
1.- Starting at an appropriate place a “long-term” monitoring of L. cervus (or P. barbarossa) populations. This can be done in several ways: (a) by quantifying the abundance of any of those species in parks or gardens, (b) by quantifying mortality in roads (see improved protocol), (c) by sampling at dusk in appropriate places, using the transect to estimate the abundance of Lucanus cervus, or (d) combining the live traps (see also the bottle-trap) with mark-recapture procedures.

References

Fuller, R. J.; Gregory, R. D.; Gibbons, D. W.; Marchant, J. H.; Wilson, J. D.; Baillie, S. R. & Carter, N. 1995. Population declines and range contractions among lowland farmland birds in Britain. Conserv. Biol. 9: 1425-1441.

Hildén, O. 1987. Finnish winter bird censuses: long-term trends in 1956-1984. Acta Œcol. Œcol. Gen. 8: 157-168.

Krebs, J. R. 1989. Ecological methodology. 2ª ed. Harper Collins, New York.

Pimm, S. L. 1994. The importance of watching birds from airplanes. Trends Ecol. Evol. 9: 41-43.

Pollard, E.; Hall, M. L. & Bibby, T. J. 1986. Monitoring the abundance of butterflies 1976-1985.

Robbins, C. S.; Droege, S. & Sauer, J. R. 1989. Monitoring bird populations with Breeding Bird Survey and atlas data. Ann. Zool. Fenn. 26: 297-304.

Siriwardena, G. M.; Baillie, S. R.; Buckland, S. T.; Fewster, R. M.; Marchant, J. H. & Wilson, J. D. 1998. Trends in the abundance of farmland birds: a quantitative comparison of smoothed Common Birds Census indices. J. Appl. Ecol. 35: 24-43.

Stefanescu, C. 2000. El butterfly monitoring scheme en Catalunya: los primeros cinco años. Treb. Soc. Cat. Lep. 15: 5-48.

Taylor, L. R. 1986. Synoptic dynamics, migration and the Rothamnsted Insect Survey. J. Anim. Ecol. 55: 1-38.