Preventative Fire Procedures in Mediterranean Woods Are
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J Insect Conserv DOI 10.1007/s10841-008-9177-y POINT-OF-VIEW Preventative fire procedures in Mediterranean woods are destroying their insect Biodiversity: a plea to the EU Governments J. A. Quartau Received: 23 November 2007 / Accepted: 16 June 2008 Ó Springer Science+Business Media B.V. 2008 Mediterranean forests and shrubland have been burned Clearly, through the present detrimental practice, the down by more and more frequent and intensive summer obvious result will be the loss of an important proportion of fires during the last decades (Ramade 1990; Blondel and the arthropod biodiversity in Portugal. In fact, although Aronson 1999). Portugal, where forests and woods make forest size has obviously effect, the most important factor about 2/3 of its continental territory, is no exception since in conserving woodland insects is the amount of under- forest fires have been also catastrophic there in part as a storey vegetation (Dennis et al. 1995). result of large continuous tracts with high tree density and Thus, many already rare insect species are expected to understorey development that facilitate fire access to tree dwindle in numbers or even become extinct in a country canopies. with a high rate of endemicity and where more than half of With a view to the prevention and management of these its presumed entomofauna, totalling up to about 30,000 fires, the Government published a recent law (Decreto-Lei species, is yet to be recognized or even described to science no. 124/2006) which, among a complex set of other man- (Quartau and Carvalho 1998). agement measures, establishes rules for the mandatory Taking the example of the families within the Hemiptera clearance of the forest vegetation. The law, however, does Cicadomorpha and Fulgoromorpha, more than 40 species not contemplate any strategy to conserve the woodland were recorded by Seabra (1931) in just one tract of Pinus biodiversity (ground flora and the associated fauna). In the pinaster in the area of Leiria. Within the former group, meanwhile, a number of small and medium enterprises immediately comes to my mind about half a score of (SMEs) have emerged and have followed an extreme endemic species mostly associated with grasses of the ‘‘tidied up’’ regime through which they thoroughly remove understorey that might be under the risk of extinction. So, across all the forest patch the entire ground cover made up within the Cicadellidae the following endemic leafhoppers of shrubs, herbaceous plants and grasses and in a way that mostly occur in the undergrowth of pine woods (Pinus the litter layer of the forest floor is also severely damaged. pinaster) and chestnut woods (Castanea sativa): Adarrus Hence, the entire associated forest-dwelling fauna (mostly beirae Lindberg, Mocydiopsis nigrolineata Remane, insects and other arthropods) is also removed. These Lusitanocephalus sacarraoi Quartau, Agallia linnavuorii ‘‘tidying up’’ operations strongly contrast with the tradi- Quartau and Jassargus remanei Quartau (Quartau 1970, tional management regimes of a few decades ago, where in 1971, 1986; Nast 1987). A similar situation occurs with pinewoods, for instance, practically only the broken bran- cicadas, which oviposit in many cases on herbaceous plants ches, dead needles and pine cones were taken by occurring in pine woods (Pinus pinaster and P. pinea) and landowners for fuel. in olive groves (Olea europaea). Of the 13 distinct cicadas recognized in Portugal, the following four are endemic and with the exception of the last one, all have small popula- J. A. Quartau (&) tions restricted to a few woodland sites in Portugal: Depto. de Biologia Animal/Centro de Biologia Ambiental, Euryphara contentei Boulard, Tettigetta estrellae Boulard, Fac. de Cieˆncias de Lisboa, C2, Campo Grande, 1750 Lisbon, Portugal T. mariae Quartau & Boulard and Cicada barbara lusita- e-mail: jaquartau@fc.ul.pt nica Boulard (Quartau and Fonseca 1988; Sueur et al. 123 J Insect Conserv 2004). Our knowledge on the other groups of forest- understorey and floor strata also causes the removal of the dwelling insects in Portugal is still poor and fragmentary, natural enemies (predators and parasitoids of phytophagous but all evidence points to the fact that such entomofauna insects), which use various available resources in such follows a similar pattern as pointed out with the Cicado- layers, namely in their development or in finding shelter morpha and is as rich and diverse as elsewhere in southern and overwintering refuge. It is well known that such pre- Europe. For instance, the Microcoryphia has got several dators and parasitoids feed on other insects and play an woodland species such as Dilta machadoi Bitsch, a narrow- important role to prevent populations from reaching the range taxon occurring in pine woods (Bitsch 1966; Mendes pest status. So, it is not surprising that the removal of 1976). Collembola occur in a great variety of habitats and natural enemies constitutes one of the important factors are quite important components of the forests floor. that may cause pest outbreaks (e.g. Price 1987; Risch 1987; Examples of endemic or narrow-range species occurring in Speight et al. 1999). Moreover, when these are removed Portuguese pine woods are, for instance Proisotoma gisini from forest patches contiguous to crops, it is not unrea- Gama, Gamachorutes verrucosus Cassagnau and Lepido- sonable that agricultural pests might also be induced. cyrtus lusitanicus Gama (da Gama 1964; da Gama et al. In addition, even a greater threat to the Portuguese insect 1997). Coleoptera also contain woodland endemic species biodiversity is the recently announced industrial exploita- such as Geocaris portalegrensis Serrano & Aguiar, an tion of forest biomass to get energy. Here everything is to endogeous carabid found in Pinus pinaster patches or be cleared across the forest patches: trees, bushes, herbs interesting chrysomelids found in a variety of open woods and grasses, as well as dead leaves, broken branches and such as Labidostomis lusitanica (Germar), Cryptocephalus decaying or dead wood. Perhaps this will wreck most forest tristigma Charpentier and C. celtibericus Suffrian (Serrano habitats in the country and, if not regulated, the overall loss 1981; Serrano and Aguiar 2000; Serrano et al. 2002). With will be impressive. All this dramatically contrasts with the respect to the Diptera, Ribeiro (1990, 1992) has found EU0s objective of halting biodiversity loss by 2010 (cf. mycetophilids mostly in pine woods, such as Bolitophila Convention on Biological Diversity 2001; UNEP 2002)! pseudohybrida Landrock, Cordyla styliforceps (Bukowski) As such, entomologists and ecologists from other south or Exechia peyerimhoffi Burghele-Balacesco. In the Lepi- European countries—where intense summer fires rage out doptera, where much data are still lacking for the of control more and more frequently and where similar Heterocera, several examples of forest-dwelling species are detrimental procedures for the prevention of fires might known in the Rhopalocera, as in those associated with the also be put into practice—are strongly requested to make herbaceous layer of Quercus pyrenaica woods, for instance urgent pleas to the European Commission and the IUCN. In the threatened nymphalids Brenthis ino (Rottemburg), short, pressure should be made on the EU Governments in B. hecate (Denis & Schiffermueller) or the also threatened order to introduce in their fire management bills (and in Hemaris lucina (Linnaeus), together with several grass- regulations dealing with the exploitation of the forest bio- feeder satyrids or the papilionid Zerynthia rumina (Lin- mass) sound habitat management procedures that may naeus) and the lycaenid Callophrys rubi (Linnaeus) whose safeguard the conservation of what still remains of the larvae feed on herbaceous plants for instance in pine woods formerly rich insect biodiversity of the Mediterranean (Maravalhas 2003; Bivar de Sousa and Patrı´cia Pereira, woodlands (Balletto and Casale 1991). pers. com.). Finally an important group of insect related Broadly speaking, the present law (Decreto-Lei no. 124/ arthropods are the numerous spider species also found 2006) establishes for the prevention of forest fires, among associated with woodlands. Examples are several dysderids other measures, mosaics of woodland patches at two scales: and gnaphosids, some still undescribed (Cardoso et al. (i) forest tracts larger than 500 ha should be separated by 2008, pers. com.), and the recently found Malthonica strips 125 m wide, where the trees, shrubs, herbs and litter oceanica Barrientos & Cardoso, an endemic agelenid of the are removed; and (ii) at a smaller scale, forest patches not floor of woods dominated by Quercus faginea and Q. suber bigger than 50 ha each (in general between 20 and 50 ha; (Barrientos and Cardoso 2007). from 1 to 20 ha in the cases of greater risk of fire) should All these are just a few examples of what is surely of a be separated by cleared rides 10–50 m wide (exceptionally much wider range. It is not unreasonable, therefore, that the 100 m) also with all the vegetation removed. The width of present ‘‘sanitation’’ regime followed so far by many SMEs, the gap separating adjacent patches would depend on the forest managers and landowners alike may put, as referred type of the edge patch, whether it confines with roads, rails, to before, an unprecedented large number of insect species buildings, villages, etc. As reforestation the law favours the under the risk of extinction, many of which are endemic to plantation of deciduous trees. Yet, as referred to before, no Portugal (or the Iberian peninsula) or have restricted ranges. concern with the conservation of the biodiversity is shown. Beyond this already gloomy scenario, insect pest out- Therefore, in order to prevent the extreme regime of breaks might also be induced, since the clearance of the removing all the understories across each patch, which has 123 J Insect Conserv been followed by SMEs and foresters, the law should also factors in conserving woodland insects and can also act as establish as mandatory a few measures for biodiversity dangerous inflammable materials.