Corrigenda

Entomologica Fennica. 3 July 200

Lepidoptera collected in the Canadian Arctic during the Tundra Northwest 99 expedition

During the Swedish-Canadian icebreaker-based expedition to the Nearctic in summer 1999 (July and early August), moths and butterflies (Lepidoptera) were collected during short, helicopter-aided visits to eight sites in the Canadian archipelago, three sites on the Canadian mainland near the arctic coast and also at Thule Air Force Base in north Greenland. Some of the visited sites (notably those on Melville Peninsula, Somerset Island and King William Island) have not previously been investigated with respect to their insect faunas. Several records thus represent species range extensions. They generally corroborate an earlier hypothesis, based on a floristic zonation scheme, which has been used as a framework for understanding the distribution of Arctic butterflies

Convergence in wing coloration between orange underwing moths (Archiearis spp.) and tortoiseshell butterflies (Aglais spp.)

We analysed the wing coloration of the orange underwing moth Archiearis parthenias (Geometridae, Archiearinae) in comparison with the small tortoiseshell butterfly Aglais urticae (Nymphalidae). Both species fly in early spring and occur sympatrically in the northern Palaearctic. Aglais, the more common species, has a longer flight period and uses a broader range of habitats. Both species show a camouflaged colour pattern on surfaces exposed at rest but a bright orange signal in flight. Although the evolution of its coloration is constrained by its geometrid morphology, Archiearis is functionally similar to Aglais both while resting and in flight. Archiearis has presumably evolved from nocturnal geometrid ancestors. Its shift to diurnality has included a change in the predator defence system from one based on ultrasonic hearing, functional against bats, to one presumably functional against birds. Preliminary palatability tests showed that Aglais is distasteful to birds (chicken), while Archiearis seems to be palatable. The function of the convergent coloration is unknown, but several possibilities are discussed

Testing the performances of automated identification of bat echolocation calls:A request for prudence

Echolocating bats are surveyed and studied acoustically with bat detectors routinely and worldwide, yet identification of species from calls often remains ambiguous or impossible due to intraspecific call variation and/or interspecific overlap in call design. To overcome such difficulties and to reduce workload, automated classifiers of echolocation calls have become popular, but their performance has not been tested sufficiently in the field. We examined the absolute performance of two commercially available programs (SonoChiro and Kaleidoscope) and one freeware package (BatClassify). We recorded noise from rain and calls of seven common bat species with Pettersson real-time full spectrum detectors in Sweden. The programs could always (100%) distinguish rain from bat calls, usually (68–100%) identify bats to group (Nyctalus/Vespertilio/Eptesicus, Pipistrellus, Myotis, Plecotus, Barbastella) and usually (83–99%) recognize typical calls of some species whose echolocation pulses are structurally distinct (Pipistrellus pygmaeus, Barbastella barbastellus). Species with less characteristic echolocation calls were not identified reliably, including Vespertilio murinus (16–26%), Myotis spp. (4–93%) and Plecotus auritus (0–89%). All programs showed major although different shortcomings and the often poor performance raising serious concerns about the use of automated classifiers for identification to species level in research and surveys. We highlight the importance of validating output from automated classifiers, and restricting their use to specific situations where identification can be made with high confidence. For comparison we also present the result of a manual identification test on a random subset of the files used to test the programs. It showed a higher classification success but performances were still low for more problematic taxa

Vision complements echolocation in an aerial-hawking bat

The northern bat Eptesicus nilssonii normally hunts flying insects in the air using frequency-modulated echolocation calls. It is also known to detect and catch visually conspicuous prey (white moths) hovering low among grass stalks. To overcome the problem with acoustic clutter from the grass, which interferes with target echo detection, the bats make use of visual cues in addition to those of echolocation. We therefore investigated the minimum size of prey that the bats could distinguish by using vision, by presenting the bats with different sized dead and spread moths. We found that vision increased the chance of detection only when the moths had a wingspan of at least 5 cm. Smaller targets were detected using echolocation alone. The mean detection range was 3.5 m, suggesting that the bats need a visual acuity of 49′ of arc to detect the prey. This is consistent with results of optomotor response tests and counts of retinal ganglion cells in closely related species. Our results suggest that the visual acuity of Eptesicus bats may not be adequate for prey detection under normal conditions, but that the bats can use vision when the prey is unusually large and conspicuous. The northern bats display a flexibility in prey detection techniques not previously recognised among aerial-hawking bats and they are able to use their full visual capacity in the field

Bat Activity at a Small Wind Turbine in the Baltic Sea

Activity of bats at an old wind park four km off the island of Gotland in the Baltic Sea was monitored during 50 nights from August to October 2013, using an automatic bat detector (Pettersson D500-X) mounted on one of the turbines. Single individuals or pairs of common noctules Nyctalus noctula were recorded on five occasions only (26 and 27 August), all in calm weather and when little or no rotor movement occurred. Since such conditions were unusual (five of 50 nights of observation) the visits by the bats were unlikely to be chance events (migrating bats passing the turbine), but more likely involved bats attracted to the turbines. However, no feeding buzzes were recorded and the bats never stayed near the turbine more than one minute. The turbines studied are lit by 250 W white lights and this could have been the reason why bats visited the turbines, because such lights potentially attract insects. The bats could not have been attracted to the turbines by any factor related of the movement of the rotor or the generator, such as Doppler-effects, noise, heat or electric fields

När natt blir dag : Belysning av av kyrkor och brunlångörats försvinnande - kunskapsunderlag för handläggning av artskydd

Äldre kulturbyggnader har nästan alltid inneboende fladdermöss. Ibland finns flera arter i olika delar av byggnaden. De kan finnas i tak, på vindar och i torn, i källarvalv eller i springor i fasaden, allt beroende på art och årstid. Den i särklass vanligaste arten i svenska kyrkor är brunlångöra Plecotus auritus. Sommartid bor de antingen enstaka (hanar) eller i kolonier med honor och ungar (yngelkolonier). Fladdermöss och deras boplatser har ett strikt skydd i EU, inklusive Sverige. Estetisk belysning (fasadbelysning) av kyrkor innebär en konflikt med artskyddsförordningen, eftersom den gör kyrkan obeboelig för fladdermöss. Den här skriften förklarar hur problemet uppstår och vad man ska göra åt det. Den är tänkt att vara en handledning för dem som på något sätt har att hantera fladdermöss i kyrkor och andra kulturbyggnad

Photography as a low-impact method to survey bats

Bats are mammals of chief conservation concern and also represent potentially powerful bio-indicators. Surveying bats is thus an important task but the approaches adopted may either be too invasive (capture) or prone to identification errors (acoustic methods). We here report on the use of a photographic trap to survey bat species richness we tested at two drinking sites in central Italy. The species richness we estimated was similar to that obtained by a previous mist-netting effort at the same sites. We also photographed species often overlooked in acoustic surveys due to their faint echolocation calls. From the photographs we could frequently identify sex, reproductive status, age class and individual marks. Given the relative non-invasiveness of this approach, we strongly recommend it in lieu of capture at sensitive sites or to complement acoustic surveys in order to improve identification rates. (C) 2014 Deutsche Gesellschaft fur Saugetierkunde. Published by Elsevier GmbH. All rights reserved

Vision complements echolocation in an aerial-hawking bat

The northern bat Eptesicus nilssonii normally hunts flying insects in the air using frequency-modulated echolocation calls. It is also known to detect and catch visually conspicuous prey (white moths) hovering low among grass stalks. To overcome the problem with acoustic clutter from the grass, which interferes with target echo detection, the bats make use of visual cues in addition to those of echolocation. We therefore investigated the minimum size of prey that the bats could distinguish by using vision, by presenting the bats with different sized dead and spread moths. We found that vision increased the chance of detection only when the moths had a wingspan of at least 5 cm. Smaller targets were detected using echolocation alone. The mean detection range was 3.5 m, suggesting that the bats need a visual acuity of 49′ of arc to detect the prey. This is consistent with results of optomotor response tests and counts of retinal ganglion cells in closely related species. Our results suggest that the visual acuity of Eptesicus bats may not be adequate for prey detection under normal conditions, but that the bats can use vision when the prey is unusually large and conspicuous. The northern bats display a flexibility in prey detection techniques not previously recognised among aerial-hawking bats and they are able to use their full visual capacity in the field