Bats (Chiroptera) are one of the most numerous mammalian order, bats have high conservation status and most of the species are considered to be rare and endangered animals. In West Europe countries bats are recognized as valuable indicators of nature ecosystems conditions (http://www.bats.org.uk/pages/bats_as_indicators.html, http://www.ibats.org.uk/).
Like all groups of threatened species bats need clear assessment of changes taking place in their population, and it can be done via monitoring including estimation of some quantitative population parameters.
There are mainly two approaches of monitoring programs which are applied in the world: acoustic monitoring, using bat detectors and visual monitoring with regular survey of potential summer and winter roosts of bats. But these methods are remote techniques and provide only fragmentary data about bat number and relative abundance at present moment, without data on the population structure.
Winter surveys in hibernacula sites are more often used method in Ukraine. Unitized and standardized conception of summer bat population monitoring in Ukraine appears to be undeveloped. Bat species composition and structure of assemblage are still unknown at many nature protected territories of Ukraine.
The program of inventory and monitoring of bats was started in 2008 on the territory of National Nature Park (NNP) “Gomolshanskie lisy”(Kharkov region), for which 10 bat species were known. We compared data on effectiveness of different methods of bat survey (mist net, plastic trap, ultrasound detector) which were used in NNP «Gomolshansky lisy» during 1999–2007. We revealed that the most effective method for the study of species composition and population structure of bats was mist net capture. We decided to check if it is possible to reveal all known bat species for this territory in a short period of time (in July) using standardized scheme of mist nets capture. July is the best month for primary inventory because young bats begin to fly but the autumn migration hasn’t started yet. And it was successfully realized; we obtained 504 specimens of all 10 known bat species during only two weeks of the mist netting.
The essence of method of inventory is two successive series of capture of bats with using of mist nets on the territory approximately 400-500 ha. Both series should be conducted in July at ten mist net points in typical for the study site biotopes.
Parameters for future summer monitoring of bats:
Species composition – disappearance or appearance of bat species is a key parameter of the monitoring.
Relative species abundance – (part of each species in general sum of captured bats) temporal changes of this parameter allow to judge about decrease or increase of abundance of some species. Also, comparing pattern of relative species abundance at different localities allows to judge about habitat preference by bat species.
Relative numbers – (general meaning of index “number of bats captured per hour”) reflects the bats abundance at the territory and allow to track general dynamics of group number.
Index “bats per hour” for each species – this parameter reflects abundance of every species and allows to compare different habitats and periods, the temporal changes of the parameter also provides subtle indirect data about the species status.
Breeding status of the species – state of reproductive organs of adult bats and presence or absence of juvenile individuals can reflect if the species breed there and how local conditions are adequate for their biological demands. Changes of this parameter can give important information both about role of the study region in reproduction of the species and about tendencies of population development.
Sex ratio of adult and subadult bats – important parameter for understanding distribution pattern of sex-age groups within species reproductive range.
Inventory success indicator – the number or percent of successful mist-netting nights (when at least one bat was captured), and the total number of specimens per capture.
Complex of parameters of growth and development of young bats and weight of adults – reflect the influence of climatic factors of present year on bats, temporal changes of this parameter could reflect influence of climate changes on bats.
Primary inventory (revealing of all of these parameters) is a first step to further monitoring of bat populations. After repeated inventory at the same research territory 3-4 years later we could obtain information about temporal changes of these parameters and thus realize monitoring of summer bat population on the given territory.
At the moment the primary inventory of summer bat population was conducted at five study sites (fig.2), four of them on the territory of Ukraine and one in Russia.
We received data on 16 bat species (Tab.1) and 1869 bats were captured during the research work. All captured bats from three out of five study sites were ringed and obtained data were given to Ukrainian ringing center (Kyiv, Ukraine).
Table 1. The list of all involved in the present project species of bats (2008-2010) and their status
№ Species Status
1 Myotis myotis Greater mouse-eared bat +
2 Myotis dasycneme Pond bat +
3 Myotis brandtii Brandt’s bat +
4 Myotis mystacinus Whiskered bat +
5 Myotis daubentonii Daubentin’s bat ++
6 Myotis nattereri Natterer’s bat +
7 Myotis bechsteinii Bechstein’s bat +
8 Nyctalus noctula Noctule ++
9 Nyctalus leisleri Leisler’s bat ++
10 Barbastella barbastellus Barbastelle +
11 Pipistrellus pygmaeus Soprano pipistrelle +
12 Pipistrellus nathusii Nathusius’ bat ++
13 Vespertilio murinus Parti-colored bat ++
14 Eptesicus serotinus Serotine +
15 Plecotus auritus Brown long-eared bat +
16 Plecotus austriacus Grey long-eared bat +
«++», «+» – species of bats involved in the system of inventory and future monitoring
“++” – mass indicator species
Fig. 2. Map of study sites of primary bat inventory
№ Study site Year Number of species Number of bats
1 National Nature Park “Gomolshanskie lisy” 2008 10 504
2 Naturу Reserve “Yaremovskoe” 2009 10 660
3 National Nature Park “Galytskiy” 2010 9 30
4 Chernobyl Exclusion Zone 2010 7 434
5 National Park “Smolensk Lakeland” 2010 8 241
Program coordinators:
Alona S. Gukasova gukasova at ukr.net
Anton S. Vlaschenko vlaschenko at yandex.ru
Interdepartmental research laboratory
“Study of biodiversity and development of nature reserve management”, Kharkov city
ADDITIONAL INFORMATION:
Information about bats: http://www.kazhan.org.ua/ukr/species.htm
Main scientific papers on results of research:
Vlaschenko A.S. and A.S. Gukasova. 2009. Development of method for the inventory of species composition and population structure of bats // Nature reserves in Ukraine. 15(1): 49-57 [in Russian]
Vlaschenko A.S. and A.S. Gukasova. 2010. Bat (chiroptera) fauna and structure of assemblage of projecting protected area “Yaremovskoe” (Kharkov region)// Nature reserves in Ukraine. 16(2): 64-70 [in Russian with English summary]
Gukasova A., Vlaschenko A. 2010.Bat fauna primary inventory and monitoring using mist nets.//15th International Bat Research Conference (August 23-27, 2010, Prague): 157
– Photo from expeditions: