0000000000056727
AUTHOR
Viesturs Vintulis
Body weight provides insights into the feeding strategy of swarming bats.
Temperate bat species that hibernate in underground sites are known to visit hibernacula in late summer where they perform an activity known as "swarming". We analysed trends in body mass-to-forearm ratio - the body condition index (BCI) - to investigate whether bats arrive at swarming sites following intensive nocturnal feeding. In a two-year study, Myotis daubentonii, M. brandtii and M. dasycneme were captured by mist-net at one swarming site from late July until early October. In late summer, the BCIs of captured males, females and subadult bats were positively correlated to the time of their capture during the night. In September, adult bats had higher BCIs than in late summer and the B…
IMPORTANCE OF BAT UNDERGROUND ROOSTS AND LONG-TERM CHANGES OF BAT POPULATIONS IN LATVIA
Anotācija Darbā aplūkotas trīs tēmas: sikspārņu ziemošanas mītņu raksturojums, šo mītņu izmantošana dažādās sezonās un ziemojošo un migrējošo sikspārņu populāciju skaita izmaiņas. Analizēti 35 gadu laikā Latvijā ievākti dati par 994 ziemojošo sikspārņu sugu izmantotajām ziemas mītnēm. Izvērtēta šo mītņu nozīmība dažādām ziemojošajām sikspārņu sugām un aplūkota to izmantošana citās sezonās. Vislielākā sikspārņu sugu daudzveidība konstatēta alās, vislielākās ziemojošo sikspārņu populācijas – fortu tipa mītnēs un – divām sugām - mazajos piemāju pagrabos. Konstatēts, ka sikspārņi izmanto ziemošanas mītnes visa gada garumā. Divām sugām aprēķināts mazajos piemāju sakņu pagrabos ziemojošās populāc…
Phenology of Migratory Bat Activity Across the Baltic Sea and the South-Eastern North Sea
We compiled the available information on the occurrence and timing of migratory bat activity across the Baltic Sea and south-eastern North Sea coasts and islands, based on ultrasonic monitoring projects at 19 localities in 2007–2009. The data refer to three species; Nathusius' pipistrelle Pipistrellus nathusii, soprano pipistrelle P. pygmaeus and common noctule Nyctalus noctula. Pipistrellus nathusii occurred at all sites (north to 61°N in Finland), while the other species were scarcer, particularly at the northernmost sites. The status of the recorded individuals is unknown. However, the activity most likely was of migrating individuals or individuals on migration stopover, because very fe…
Transcontinental 2200 km migration of a Nathusius’ pipistrelle (Pipistrellus nathusii) across Europe
Abstract A male Pipistrellus nathusii ringed in Pape Natural Park (S Latvia) in August 2015 was recovered recently dead in Pitillas’ Lagoon Natural Reserve (N Spain) in March 2017. At 2224 km in SSW direction, this is the first documented bat migration between these countries and worldwide the longest migration record of a bat. We also report other observations of this species in autumn in Northern Spain, suggesting that the Iberian Peninsula may be an important wintering area for Nathusius’ pipistrelles. Conservation measures should be agreed on by countries along the migration routes to improve the protection of this species.
Transcontinental 2200 km migration of a Nathusius’ pipistrelle (Pipistrellus nathusii) across Europe
A male Pipistrellus nathusii ringed in Pape Natural Park (S Latvia) in August 2015 was recovered recently dead in Pitillas’ Lagoon Natural Reserve (N Spain) in March 2017. At 2224 km in SSW direction, this is the first documented bat migration between these countries and worldwide the longest migration record of a bat. We also report other observations of this species in autumn in Northern Spain, suggesting that the Iberian Peninsula may be an important wintering area for Nathusius’ pipistrelles. Conservation measures should be agreed on by countries along the migration routes to improve the protection of this species. nonPeerReviewed
RESULTS OF RADIO—TRACKING OF DUCKS IN THE LAKE ENGURE IN SUMMER 1997
ABSTRACT In summer 1997 a project of duck research using radio—telemetry was carried out on the Lake Engure, Latvia. 10 females of Mallards, 10 females of Shovelers, 9 females of Pochards and 6 females of Tufted Ducks were radio—tracked during the period from the hatching of their ducklings till fledging. Information about effect of the harness-type radio-transmitters on different species of ducks has been collected. For 15 ducks home range sizes and distances between nests and range locations were calculated. Mallards used to move further from their nest sites; one Mallard brood after one week spent near the nest site dislocated 8 km to the Southern part of the lake during one day. Problem…