Mortality of vertebrates on a road crossing the Biebrza Valley (NE Poland)

Abstract

Mortality of vertebrates was monitored on a local road running across Poland's Biebrza River Valley during 2 years (August 2005-July 2006. On the basis of distance from the river and surrounding habitats, the road (of total length 2,510 m) was divided into three stretches. The road was monitored on foot by two people every month, over a few consecutive days. A total of 1,892 road kills representing at least 47 species were found. Of these, 90.7% were amphibians, 4.2% mammals, 3.1% birds and 2.0% reptiles. Most (70%) of the amphibians were anurans, with the common toad, common frog and moor frog among them together accounting for 82% of the total. Mortality among amphibians differed between months, most anurans dying in May and August, while a majority of Urodela are lost in October. The peaks in mortality were connected with the migration of adult amphibians in spring and juveniles in summer and autumn. The number of amphibians killed was greatest on the (wettest) stretch adjacent to the river and decreased with distance from it. Mortality among birds was highest in July-probably in association with the dispersal of young individuals. Among recorded mammalian road kills, there was a prevalence of small rodents (mainly voles) and insectivores (mainly shrews). Medium-sized mammals were found only accidentally. Mortality in general was conditioned by the number of anurans killed.

Migration of amphibians and their Mortality on the road of Knyszyn forest landscape park

“…Our observation about composition of amphibians species migrating through the roads are consistent with available literature data regarding our country (Sołtysiak, Motyka 2004;Puky 2003;Gryz, Krauze 2008). By studying the migration of amphibians on the selected section of a local road in PKPK, in 2015 we found for the first time the presence of warty newt Triturus cristatus (new location of this species at the Park).…”

Road mortality of pond-breeding amphibians during spring migrations in the Mazurian Lakeland, NE Poland

“…In the majority of studies, the recorded data were based on counts made less often than once a day (Fahrig et al 1995;Orłowski 2007;Santos et al 2007;Gryz and Krauze 2008;Hartel et al 2009, reviewed by Elżanowski et al 2009). Several studies used various frequencies of counts in particular study areas (e.g., Orłowski et al 2008;Elżanowski et al 2009), and only a few counted roadkill victims once (van Gelder 1973;Hels and Buchwald 2001;Santos et al 2011) or several times per day (e.g.…”

“…Road mortality, which has increased with the expansion of road networks and the growing volume of traffic, is particularly significant (van Gelder 1973;Fahrig et al 1995;Carr and Fahrig 2001;Cooke and Sparks 2004;Gibbs and Shriver 2005;Andrews et al 2008;Carvalho and Mira 2011). Amphibians, due to their migratory behavior and rather low velocity, seem to be particularly vulnerable to road traffic compared to other vertebrates (Ashley and Robinson 1996;Glista et al 2008;Gryz and Krauze 2008). The critical period for amphibians is the breeding season when the number of animals killed on roads increases rapidly (Orłowski et al 2008).…”

Bat casualties on a road crossing a mosaic landscape

“…Usually, their share is much lower than 1%, i.e., in Great Britain: 0.2-0.3% (Hodson 1960;Slater 2002), the USA: 0.1-0.5% (Seibert and Conover 1991;Smith and Dodd 2003;Glista and De Vault 2008), and Poland: 0.1-0.2% (Bartoszewicz 1997;Gryz and Krauze 2008). Sometimes, they are absent, even in large samples of vertebrates (Clevenger et al 2003;Hell et al 2005;Najbar et al 2006).…”

“…Bats are rarely found as road casualties (Hodson 1960;Seibert and Conover 1991;Bartoszewicz 1997;Slater 2002;Smith and Dodd 2003;Coelho and Kindel 2008;Glista and De Vault 2008;Gryz and Krauze 2008). Nevertheless, as bats are much less abundant than many other vertebrates, killing by vehicles could be an important source of their mortality.…”