Urban environments as habitats for rare aquatic species: The case of leeches (Euhirudinea, Clitellata) in Warsaw freshwaters

Abstract

a b s t r a c tReduced biological diversity in freshwater habitats situated in urban areas has been discussed in numerous studies. Certain municipal areas, however, can help save animal diversity of freshwater invertebrates. In the present study animals were collected or observed alive in 13 freshwater environments localized in Warsaw -the second largest city of Central Europe -in a densely populated, urban building complex close to the city, and also in suburban areas. Leech assemblages in all the environments under observation were numerically dominated by a few common species, but on the whole 19 species were collected or observed. The populations of six rare leech species inhabit both flowing and standing waters in Warsaw. Five of these species are on the Polish Red List of Species and one is strictly protected. The shallow Lake Powsinkowskie is the richest freshwater environment in the studied area in terms of species richness and rarity and also one of the richest lakes in Poland. Taxonomic diversity in the environments under study seems not to be directly related to the size of the water body or the level of degradation but rather to the habitat complexity, especially the diversity of the bottom in littoral zone. Certain freshwater habitats located inside this great urban complex still create good conditions for rare, highly specialized species.

Flower-visitor and pollen transport networks in a large city: structure and properties

“…With the effect of increasing human pressure on natural habitats, e.g., via land reclamation and urbanization, this kind of habitat becomes prevalent in some landscapes (see, e.g., Grimm et al 2008;Seto et al 2011) and, sometimes, surprisingly, supports greater biological diversity than the surrounding habitats (Goddard et al 2010;Faeth et al 2011;Kowarik 2011). For example, large city gardens and green areas may host numerous rare invertebrates from many taxonomic groups (see, e.g., Kowalczyk et al 2004;Talley et al 2007;Matteson et al 2008;Bąkowski et al 2010;Koperski 2010). In coupling information relating to the increasing importance of urban areas in sustaining biodiversity (Grimm et al 2008;Goddard et al 2010;Kowarik 2011) with the widely reported decline in pollinators and the disruption of mutualistic networks (Kearns et al 1998;Biesmeijer et al 2006;Vamosi et al 2006;Potts et al 2010), one should be aware that understanding the structure of human-altered communities becomes an increasingly important aspect of biodiversity conservation, especially when failure to consider the ecosystem-wide context of biodiversity loss can lead to wastage of conservation resources and counterproductive management measures (Tylianakis et al 2010).…”

The first record of Piscicola pojmanskae Bielecki, 1994 in the Gulf of Gdańsk (the southern Baltic Sea) with species characteristics distinguishing it from Piscicola geometra (Linnaeus, 1758)

“…Due to high ecological tolerance, great abundance and severe damage in fish farming, leeches play an important role in freshwater reservoirs (Koperski 2010, Bielecki et al 2011), but their role in the brackish water is unknown. …”

Risk Assessment of Urban Lake Water Quality Based on in-situ Cyanobacterial and Total Chlorophyll-a Monitoring

“…Koperski [3] concluded that Lake Powsinkowskie is currently the richest freshwater environment in the Warsaw area in terms of species richness and rarity, and also one of the richest lakes in Poland. However, increased pressure from human activities can threaten the ecosystem's integrity and lead to the loss of valuable species.…”

“…The presence of urban parks, park ponds, and suburban gardens can improve the "psychological well-being of city dwellers by relieving the pressure of modern urban life" [2], and their careful management can protect rare and endangered species of, e.g., invertebrates [3]. However, (sub)urban sprawl also puts signifi cant pressure on the ecological integrity of urban lakes [3], thus also threatening the services these lakes provide to humans, such as recreation and storm water control.…”