Hydrobiologia (2009) 634:167–183 DOI 10.1007/s10750-009-9897-3 POND CONSERVATION Inter- and intra-annual variations of macroinvertebrate assemblages are related to the hydroperiod in Mediterranean temporary ponds Margarita Florencio Æ Laura Serrano Æ Carola Go´mez-Rodrı´guez Æ Andre´s Milla´n Æ Carmen Dı´az-Paniagua Published online: 5 August 2009 Ó Springer Science+Business Media B.V. 2009 Abstract Macroinvertebrate assemblages of 22 tem- length of the aquatic period for macroinvertebrates, porary ponds with different hydroperiod were sampled and three distinct wet phases of community composi- monthly during a dry year (2005–2006) and a wet year tion could be distinguished: filling phase, aquatic phase (2006–2007). Coleopteran and Heteropteran adults and drying phase. In the wet year, with a longer pond were most abundant at the end of the hydroperiod, hydroperiod, five phases could be identified, with the while Coleopteran larvae, mainly Dytiscidae, were aquatic phase differentiated into winter, early spring mostly recorded in spring. Macroinvertebrate assem- and late spring phases. Dispersers such as Anisops sar- blages differed between study years. The shorter deus, Berosus guttalis or Anacaena lutescens were hydroperiod of ponds in the dry year constrained the typical during the filling phase and Corixa affinis or Enochrus fuscipennis during the drying phase. The ponds with intermediate hydroperiod showed a similar Guest editors: B. Oertli, R. Cereghino, A. Hull & R. Miracle composition (mainly dispersers) at the beginning and Pond Conservation: From Science to Practice. 3rd Conference end of their wet period; this is not being seen in early of the European Pond Conservation Network, Valencia, Spain, 14–16 May 2008 drying or long hydroperiod ponds. A general pattern was detected, with similar variation between both M. Florencio (&) Á C. Go´mez-Rodrı´guez Á years, which may be associated with the life histories of C. Dı´az-Paniagua the macroinvertebrate taxa recorded. Don˜ana Biological Station-CSIC, P.O. Box 1056, 41080 Seville, Spain e-mail: [email protected] Keywords Aquatic macroinvertebrates Á Temporal C. Go´mez-Rodrı´guez variation Á Wet phases Á Hydroperiod Á Community e-mail: [email protected] composition Á Life cycle C. Dı´az-Paniagua e-mail: [email protected] Introduction L. Serrano Department of Plant Biology and Ecology, University of Seville, P.O. Box 1095, 41080 Seville, Spain Temporary ponds are optimal habitats for many e-mail: [email protected] macroinvertebrate species, being important for the conservation of their specialized fauna (Strayer, 2006). A. Milla´n However, these ponds have been frequently neglected Department of Ecology and Hydrology, University of Murcia, Campus Espinardo, 30100 Murcia, Spain in conservation programmes that have traditionally e-mail: [email protected] considered protection of extensive wetlands but not of 123 168 Hydrobiologia (2009) 634:167–183 small water bodies, despite their high biodiversity been described as characteristics of different pond (Collinson et al., 1995;Ce´re´ghino et al., 2008). phases; usually classified as filling, aquatic and drying Moreover, temporary ponds are highly suitable for phases, out of which the aquatic phase could be fur- ecological studies due to their wide environmen- ther differentiated into three additional phases tal gradients of salinity, temperature, vegetation, pH (Boulton & Lake, 1992; Bazzanti et al., 1996; Boix or hydroperiod (Herbst, 2001; Batzer et al., 2004; et al., 2004). Waterkeyn et al., 2008; Bilton et al., 2009). Our study has been carried out in an area in which Despite the fact that permanent ponds may contain more than 3000 water bodies support a robust network many aquatic species (Bazzanti et al., 1996; Brooks, of aquatic habitats (Fortuna et al., 2006) that exhibit 2000; Serrano & Fahd, 2005; Della Bella et al., high conservation values and encompass a wide range 2005), temporary ponds usually harbour exclusive of hydroperiod and environmental conditions (Go´mez- species or large populations of species which are Rodrı´guez et al., 2009). Several studies have focused scarce in or absent from permanent waters (Collinson on the limnology of these ponds (Garcı´a Novo et al., et al., 1995; Williams, 1997; Boix et al., 2001; Della 1991; Serrano & Toja, 1995; Serrano et al., 2006) and Bella et al., 2005;Ce´re´ghino et al., 2008). While the their use as amphibian breeding sites (Dı´az-Paniagua, dry period may exclude many aquatic organisms from 1990;Dı´az-Paniagua et al., 2005). In contrast, only temporary ponds, the absence of large predators, such preliminary data on macroinvertebrates (Agu¨esse, as fish, is a critical factor that determines the presence 1962; Bigot & Marazanof, 1966; Marazanof, 1967; of specialist taxa (Wellborn et al., 1996). Milla´n et al., 2005) and studies on abundance of Many macroinvertebrate species require an aquatic Coleoptera, Heteroptera and Odonata (Montes et al., phase to complete their complex life cycles for which 1982) have been reported. different life history strategies have been reported. In this research, we have studied temporal varia- Among the most important challenges for the macr- tion in macroinvertebrate abundance and composition oinvertebrates of temporary ponds is survival during in temporary ponds, with the following specific aims: the dry period. Some adaptations for living in (1) detecting inter-annual variation; (2) detecting temporary ponds are dispersal to more permanent seasonal variation in relation to different phases of waters, or resistance of eggs, larvae, or adults to the wet period of ponds; (3) comparing monthly desiccation (Wiggins et al., 1980). Physiological and variation within ponds of different hydroperiod and behavioural mechanisms to survive desiccation have (4) determining if there is a general pattern of also been described in different aquatic invertebrates temporal variation for all ponds in the study area. (Williams, 2006). Wiggins et al. (1980) segregated groups of macroinvertebrates according to their life history strategies, justifying the presence of specific Methods fauna in different ponds. Differences in the life history strategies of species allow the identification of The study was carried out in 22 ponds located in the functional groups which appear at different times in Don˜ana Biological Reserve (Don˜ana National Park, the ponds (Gasco´n et al., 2008) or to differences in Southwestern Spain, Fig. 1). This area is located optimal habitats, being able to only complete their between the Atlantic coast and the mouth of the life cycles in ponds with a long hydroperiod, but not Guadalalquivir River. It includes a high number of in ephemeral ponds (Schneider & Frost, 1996). temporary ponds, appearing during autumn or winter, Annual and seasonal variations of macroinverte- and two permanent ponds. The type of climate is brate assemblages have been reported in temporary Mediterranean sub-humid, with hot and dry summers, ponds (Brooks, 2000) and have been associated with mild winters, and rainfall mainly falling in autumn seasonal changes in environmental conditions during and winter (see Siljestro¨m et al., 1994, Garcı´a-Novo the wet phase (Boulton & Lake, 1992). Jeffries & Marı´n, 2006 for a detailed description of the area). (1994) found differences in the macroinvertebrate Our study period was from October 2005 to July assemblages of the same ponds in three different 2007. Annual rainfall was calculated as the amount of years, including a low rainfall year in which ponds rainfall collected from 1st September to 31st August did not fill. Different macroinvertebrate groups have of the following year. This amounted to 468.3 mm in 123 Hydrobiologia (2009) 634:167–183 169 Fig. 1 Location of the 22 temporary ponds in the Don˜ana Biological Reserve, Don˜ana National Park (SW Spain) the first year (hereafter referred to as the dry year), moment of large inundation (see Go´mez-Rodrı´guez when we sampled 18 temporary ponds which usually et al., 2008). Vegetation in the ponds was mainly dry out every summer and one semi permanent pond composed of meadow plants as Mentha pulegium L., which only dries out in years of severe drought. As Illecebrum verticillatum L. or Hypericum elodes L., this pond was dry in 2005, prior to our study period, in the littoral zone, while aquatic macrophytes were we considered it as a temporary pond. Ponds were common in deeper areas, such as Juncus heterophyl- selected to encompass the highest possible range of lus Dufour, Myriophyllum alterniflorum DC. in Lam hydroperiods, being representative of the range of & DC., Potamogeton pectinatus L. and Ranunculus ponds found in the study area. In the second year, peltatus Schrank (Garcı´a Murillo et al., 2006). annual rainfall was 716.9 mm (hereafter referred to Macroinvertebrates were sampled monthly in each as the wet year) when a higher number of ponds with pond by using a dip-net with a 1 mm mesh, netting a short hydroperiod were formed in the area. In order to stretch of water of *1.5 m length in each sampling assess the widest range of hydroperiod during the wet unit. In the wet year, the four ponds with the shortest year, we sampled three of these new ponds, although hydroperiod (including the three ponds only sampled the total number of ponds sampled was the same as during this year) were sampled every 15 days. In each the year before. In the dry year, most temporary pond, we sampled at different points along one or two ponds were wet from February to June and from transects from the littoral to the open water, the October to July during the wet year, although the number of sampling points being proportional to pond ponds with longest hydroperiod had water even size. We also took additional samples in microhabitats during August in both years. A detailed description which were not represented in these transects. The of the characteristics of Don˜ana temporary ponds, maximum number of samples per pond ranged from 6 including most of our study ponds, is given by to 13 in the month of maximal inundation.