The Importance of the CBMS in the Conservation of Catalan Butterfly
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cynthiaBulletin of the Catalan and Balearic Islands Butterfly Monitoring Scheme 2004 - no. 4 Cover illustrations contains a long article about the Orange Tip, one transect centred on the well-known sanctuary of Detail of the fore-wing underside of the Clouded of the earliest species on the wing in spring and Sant Ramon in the municipality of Sant Boi de Yellow (Colias crocea) (photo: A. Miquel). whose colours provide a touch of happiness and Llobregat. It passes through an area of Holm Oak herald the long-awaited arrival of spring. and pine woodland and scrub, and includes the Wall Brown (Lasiommata megera) roosting on a peak of the hill of the same name where many species spike of Pendulous Sedge (Carex pendula) (photo: come to hilltop. This transect complements station J.R. Salas). nº 49, which runs through the bottom of the val- The CBMS network ley. Situation of the Catalan and Oristrell (Bages comarca, 350 m): this transect Balearic Islands Butterfly lies in the easternmost part of the Sant Llorenç Monitoring Scheme in 2004 del Munt Natural Park in the municipality of Pont Editorial de Vilomara. The climate of the area is fairly con- The importance of the CBMS in the During the 11th CBMS season a notable tinental and the landscape predominantly con- conservation of Catalan butterfly landmark was reached: for the first time sists of scrub and fields, but with a highly diverse populations data was received from over 50 different collection of butterfly species. This site is an impor- stations. Almost all of the active stations in tant addition to the CBMS and it has already pro- uring Butterfly Conservation’s 5th International 2003 continued to be walked and were vided information about a number of scarce species DSymposium entitled “Lepidoptera as indicators joined by the reactivated transect at that are of great interest within the context of Cat- of Biodiversity Conservation” (Southampton, April Timoneda d’Alfés and three completely new alonia. 8 to 10, 2005) the enormous worth of the BMS transects. In all, 142,246 butterflies As well, we should mention that in 2004 record- network for documenting and understanding the belonging to 135 different species were ing recommenced in Timoneda d’Alfés (station changes taking place in European butterfly popu- recorded. nº 18) after four years of inactivity. This protect- lations was brought home to all participants. Its ed area is especially important for the relict popu- role in the conservation of these insects was high- n 2004, complete data was received from 51 lations of steppe birds and, although its butterfly lighted over and over again and this essential objec- ICBMS stations (fig. 1) and preliminary studies populations are relatively poor, they do represent tive is probably what stimulates most CBMS col- were carried out in two sites with a great potential the species found in the dry-farming areas of the laborators to walk their transects every week for for butterflies: Alinyà (1,100 m, in the comarca of Lleida plains. Given that the enlargement of the seven arduous months of the year. L’Alt Urgell) and La Vall d’Ordino (1,800 m, Andor- small aerodrome that occupies the site has been In order to contribute to the conservation of ra). It is hoped that these sites will soon enter the ruled out, it is hoped that from 2005 onwards the butterfly populations in Catalonia we must first CBMS network, although because of the spectac- area can be actively managed to favour some of the identify the causes of increases and decreases in ular diversity of butterfly species present, the learn- most important bird species (for example, Dupont’s species’ populations and, in a more general sense, ing process for recorders is necessarily somewhat Lark Chersophilus duponti). The CBMS counts dur- analyse the main causes of the wonderful butter- longer. Nevertheless, the wait will be well worth it ing forthcoming seasons, as well as data accumu- fly diversity found in our country. This is a com- as the CBMS has no data for high altitude species lated between 1995 and 1998, will provide valu- plex task that requires a large database and the abil- such as Clouded Apollo (Parnassius mnemosyne), able information regarding the response of the area’s ity to use it to full effect. In this edition of Cynthia Mountain Clouded Yellow (Colias phicomone), Pur- butterfly populations to the new management meas- we have introduced a new section that will study ple-edged Copper (Lycaena hippothoe), Geranium ures undertaken. this question in detail and provide a summary of (Eumedonia eumedon) and Silvery (Pseudoaricia Three stations became inactive in 2004: Olivel- much of the research based on our CBMS data. As nicias) Arguses, Lesser Marbled Fritillary (Brenthis la, Santiga and the Autonomous University of a start, we will look at a recent study that for the ino), Small Pearl-bordered Fritillary (Boloria selene) Barcelona. Nevertheless, the first forms part of a first time has used data from the whole CBMS net- and Common Brassy Ringlet (Erebia cassioides). rotational system with two other stations in El Gar- work to discuss patterns of diversity present in the The annual data series currently available are raf (Vallgrassa and Olesa de Bonesvalls) in which butterfly populations of Catalonia. shown in figure 2. The uninterrupted series of every year one station is ‘rested’: counts are only The results once again make it clear that but- records from many sites means that the CBMS now made for two consecutive years in each and next terflies are insects that are highly influenced by cli- has at its disposal a significant number of data sets, year Olivella will be active once again and Vallgrassa matic factors and as such act as excellent bioindi- with around 15 stations having provided data from temporarily inactive for a season. cators of phenomena that include global warming. eight or more years. On a smaller scale and in connection with habitat Habitats represented management, our results also show the degree to New transects The different habitats and plant communities sur- which butterfly communities are becoming impov- Sant Daniel (Gironès comarca, 200 m): a transect veyed by the CBMS transects in 2004 are shown erished in regions surrounded by vast areas of agri- that passes through an essentially agricultural land- in table 1. For each station, only the dominant plant culture and urban development. This tendency is scape, consisting of a mosaic of fields, pastures, communities have been taken into consideration highly worrying and provides evidence of the small fragments of Holm Oak woodland and cal- and secondary communities (those that could be negative effects of increased agricultural intensity careous scrub. The transect (length: 1,827 m) runs regarded as successional stages) are included with- and urban growth. Moreover, the interaction of around the farm of Mas Miralles in the Sant Daniel in the corresponding climax community. Thus, anthropic factors with the effects of climate change valley near the city of Girona. It is an excellent table 1 is a simplification of the real situation: for may make the situation even worse. example of an agro-pastoral area in a comarca which example, under the category “Coastal Holm Oak In this edition of Cynthia you will also find all up to now had no CBMS transect. This station woodlands” we find a great diversity of landscape the usual sections related to the workings of the receives financial support from the Consortium of types that, according to the station in question, CBMS network and to the biology and identifica- Les Gavarres. include scrublands, pine woodland, fields, dry grass- tion of our butterflies. For example, this number Sant Ramon (Baix Llobregat comarca, 300 m): lands, and so forth. More detailed information con- II Cynthia cerning the plant communities present in each sec- Fig.1. Geographical situation of all the stations that Eleventh year of the CBMS tion of the transects (with the percentage cover) have participated in the CBMS network (1994-2004), with their official number and name. Also shown is Summary of the 2004 season can be consulted in the full CBMS database. their position regarding the biogeographical regions The vast majority of CBMS stations are found of Catalonia according to generally accepted In 2004, spring was wet and summer mild, in lowland Mediterranean habitats, above all in the boundaries1. radically different weather from that of northern half of the country and in areas domi- 2003, and as a result and in sharp contrast nated by Holm Oak formations (50% of the tran- Fig. 2. Distribution of the annual series that are with preceding years, many species appeared sects). Arid and steppe-like habitats in south-west available for the different stations that have later than usual. Nevertheless, the number of Catalonia are reasonable well represented and in participated in the CBMS (1988-2004). common species with a higher (28 species) 2005 will be complemented by the incorporation or lower (31 species) annual index than in Fig. 3. Number of CBMS stations in which the 120 the previous year was similar to the of stations from the comarques of La Terra Alta and butterflies detected in 2004 (excluding the skippers respective figure from 2003. On the hand, a El Priorat. As has been mentioned elsewhere, the (Hesperiidae), since this group is not recorded in the stations at sea-level (including those in the Balearic same way in all transects). clear tendency towards more butterflies but Islands) provide plenty of good information on fewer species per station was noted. Finally, migrant species. In recent years, a special empha- Table 1. Habitats and plant communities represented it is worth highlighting the significant sis has been put on establishing stations in the Pyre- in the CBMS in 2004, with the number of stations decrease in the numbers of migratory butterflies (in some cases reaching nees and it is hoped that during 2005 and 2006 as they appear in.