Impacts of selective logging on frogs in a forested area of northern New South Wales Francis Lemckert* Native Forest Management Systems, Forest Research and Development Division, State Forests of New South Wales, PO Box 100, Beecroft, NSW 2119, Australia Received 21 March 1998; received in revised form 2 September 1998; accepted 18 September 1998 Abstract Counts of frogs were performed at 52 streams and 33 ponds in the Dorrigo area of northern New South Wales, Australia. Three measures of logging disturbance and seven other environmental features were recorded for each site to determine if any of these factors signi®cantly in¯uenced species richness (number of species) or abundance of individuals breeding at either streams or ponds. Species were also categorised into ®ve ``guilds'' and the number of species of each guild compared to the same factors. Altitude and longitude were found to have the greatest in¯uence on total species richness. The percentage of undisturbed forest was also a sig- ni®cant variable with species richness increasing in more disturbed areas. Increasing numbers of logging events increased the species ``richness'' of tree frogs and generalist species at streams and more recent disturbances appeared to increase the richness of gen- eralists at ponds. No single habitat feature was found to consistently explain individual species abundances at ponds or streams. Logging activities appeared to favour several species, but negative eects of logging were also recorded for three species. The great barred frog Mixophyes fasciolatus decreased in numbers in more recently logged areas, the giant barred frog Mixophyes iteratus decreased in abundance in recently-logged areas and at sites where little undisturbed forest was available and the tusked frog Ade- lotus brevis appeared to be dependant on patches of undisturbed forest. The results indicate that selective logging has little impact on many frog species, but large forest-dependent species and terrestrial breeders are more likely to be negatively aected. # 1999 Elsevier Science Ltd. All rights reserved. Keywords: Frogs; Logging impacts; Species richness; Abundance; Conservation 1. Introduction In recent years, signi®cant concern has arisen over the evident declines in amphibian populations throughout the world (Blaustein and Wake, 1990; Tyler, 1991; Bee- bee, 1992). The cause of most declines is uncertain, and in many cases a range of factors may have been involved (Pechmann and Wilbur, 1994). However, at least some declines have been attributed directly to human activ- ities including the disturbance and destruction of forests for timber supplies (Means et al., 1996; Pearman, 1997). Studies in North America have found that terrestrial amphibians (mainly salamanders) are more diverse and abundant in areas of unlogged or old growth forest (Enge and Marion, 1986; Pough et al., 1987; Petranka et al., 1993). These studies have indicated that reductions in amphibian diversity and abundance after forestry operations may be attributed to changes to features of the environment such as hardwood shrub abundance (Corn and Bury, 1991; Welsh and Lind, 1995), leaf litter depth (Heatwole, 1962; Pough et al., 1987) or the type and the amount of coarse woody debris (Welsh and Lind, 1991; Petranka et al., 1993). De Maynadier and Hunter (1995) reviewed the published studies on for- estry impacts and found that salamanders (urodeles) were more prone to declines than were frogs (anurans). These workers also found that clear cutting and planta- tions were likely to be more detrimental to amphibians than less intensive forms of forestry, but that this was dependant to some degree on the retained features of the forest such as the level of retained woody debris. Overall, the results of these studies indicate that forestry can be an important consideration in the long-term conservation of forest-dependant amphibians. As ecto- thermic vertebrates represent a highly signi®cant trophic level within any environment (Pough, 1980), the loss of 0006-3207/99/$ - see front matter # 1999 Elsevier Science Ltd. All rights reserved. PII: S0006-3207(98)00117-7 Biological Conservation 89 (1999) 321±328 * E-mail: frankl@ironbark.forest.nsw.gov.au