| dc.description.abstracteng | In the past 20 years, bat carcasses have been collected and conserved by deep-freezing. This was initiated by the environmental conservation agency in Lower Saxony (Federal Republic of Germany), now called Niedersächsisches Landesamt für Ökologie (NLÖ). For the first ti-me, a complete inventory of the available 458 bat carcasses from 13 different species were listed and registered in an ACCESS-data bank. A residue analysis was conducted on the Common pipistrelle (Pipistrellus pipistrellus) and the Greater-Mouse-Eared bat specimens (Myotis myotis), taking into account the physical condition and the sample scope, to determine the heavy metal contamination for the period 1987 to 1999. The lead content found in forarms of 111 Common pipistrelle and 30 Greater Mouse-Eared bats was determined. Heavy metal levels from the lung, liver and kidney tissue were taken from 22 P. pipistrellus, as well as, from the hair specimens from 95 P. pipistrellus. In additi-on, 48 excrement samples, taken from various locations, were tested. A 50 % decline in the lead content of the bone tissue within the test period (1987-1999) was found. The lead content measured in the hair specimens, in the same time frame, declined by 55 %. The most substantial reason for this decline in the lead pollution is most probably the introduction of lead-free gasoline in 1988. Based on recent neurobehavioral investigations on primates, the connection between the dramatic bat population reduction up until 1988 and lead contamination has been discussed. Even minimal lead levels in the subtoxic area, lead to a si-gnificantly less-efficient nervous system. Therefore, the interpretation of acoustic stimuli in coordinated motion, will be delayed. For the bat, which greatly depends on it´s hearing for food-finding, the increased lead intake, due to the increased use of leaded gasoline in the first half of the 20th century could have had a tremendous effect. Animals from regions with higher lead pollution levels show significantly higher lead content in bone, as well as, liver and kidney tissue. Gender differences were not found. The lead level found in P. pipistrellus was 70% higher than in M. myotis. The lung tissue taken from animals from the lead polluted regions did not show increased contents. Inhalation does not seem to be a major factor. A decline in the cadmium (40 - 50 % decline) and the nickel (appr. 10%) could also be de-termined for the period 1987-1999. No recognizable trend was seen for the remaining ele-ments tested (chrome, copper and zinc). Random sampling for platinum, increasingly released into the environment since the introduc-tion of the automobile catalytic converter, detected 2,6 ng/g in hair and 6,8 ng/g TS in excre-ment. Platinum content in bone tissue was under the detection limit. (< 0,5 ng/g TS). The accumulated data will be compared to national and international literature. Based on all data, reference-ranges have been created which represent the heavy metal content middle va-lues. | de |