Anmerkungen zur Bestandsentwicklung des Uhus (Bubo bubo) in Bayern

Zusammenfassung In zwei Kerngebieten des Uhuvorkommens der Bundesrepublik Deutschland hat der Uhu in neuester Zeit scheinbar sehr stark zugenommen. In der Frankenalb (10 000 km²) schätzte man von 1955 bis 1964 etwa 30–40, Anfang der 70er Jahre etwa 50 und 1975–1980 75–83 Paare. In einem Ausschnitt der mittleren bayerischen Alpen (ca. 840 km²) waren um 1937 nur 3 Brutpaare bekannt, um 1975 mindestens 4; 1983/84 konnten jedoch mindestens 14 Brutpaare ermittelt werden. Die Zunahme ist zumindest größtenteils auf intensivere und systematische Kontrollen zurückzuführen. Der für die 30er Jahre vermutete Tiefstand des Bestandes in der Bundesrepublik dürfte weit höher gelegen haben als bisher vermutet, da zeitgenössische Quellen wahrscheinlich nur Teile des Bestandes erfaßten. Sicher lag der Bestand im 20. Jahrhundert wohl nie unter 50 Brutpaaren (bisherige Annahme 35), selbst zur Zeit des Minimums in der Bundesrepublik wahrscheinlich deutlich höher. Eine Obergrenze des bayerischen Brutbestandes von 200 Brutpaaren um 1980 ist durchaus realistisch. In den Alpen ist auch heute noch der Brutbestand völlig unzureichend bekannt. Das Aussetzen von Uhus hat in Bayern sicher keine Bedeutung für die Bestandsentwicklung gehabt. Der Median liegt für Todfunde ausgesetzter Uhus bei 0,43, für als Nestling beringte Wilduhus bei 1,9 Jahren. An Leitungen starben hochsignifikant mehr Wildvögel, an Straßen und Eisenbahnen dagegen hochsignifikant mehr ausgesetzte Vögel. Unterschiedliche Wanderneigung zwischen Wilduhus und ausgesetzten Vögeln ließ sich nicht sichern. Aussetzung und Wiedereinbürgerung sollten in Süddeutschland unbedingt unterbleiben und dürften auch im mittleren und nördlichen Deutschland mittlerweile überflüssig geworden sein. Eine Bestandsüberwachung und Kontrolle in ausgewählten Gebieten ist dagegen vordringlich.

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Some remarks on long term trends in the breeding population of the Eagle Owl (Bubo bubo) in Bavaria

Summary In two centres of its distribution in the Federal Republic of Germany the Eagle Owl has increased remarkably in recent years. Between 1955 and 1965 the population of the Frankonian Jura (ca. 10 000 km²) was estimated between 30 and 40 pairs, at the beginning of the seventies about 50, and in 1975/80 about 75–83 pairs. In an area of the Bavarian Alps (ca. 840 km²) only 3 pairs were known in 1937, at least 4 in 1975. In 1983/84, however, a thorough examination revealed at least 14 pairs in this area. The increase in both areas is most likely due to intensive and systematic checks in recent years. The lowest population level in the FRG, supposed for the thirties, was probably higher than estimated so far as contemporary sources apparently did not cover the whole population. During the 20^th century the population total of the FRG most likely has never been below 50 pairs and was probably higher even in times with minimum level. For 1980 an upper limit of 200 pairs in Bavaria seems to be realistic. In the Alps, however, the population size remains unsufficiently known even today. Release of captive bred birds didn't seem to have any increasing and stabilizing effect on the Bavarian population. The median for released birds found dead was 0,43, for wild chicks 1,9 years. Significantly more released birds died by traffic, whereas significantly more wild birds were victims of overhead lines. Differences in dispersal between wild and released birds seem likely, but could not be proved statistically. Releasing resp. reintroduction should be stopped in southern Germany; even in middle and northern Germany this conservation strategy seems to be unnecessary today. Survey and protection of breeding sites, however, should be continued or reorganized.

     

Carbohydrates of influenza virus. Structural elucidation of the individual glycans of the FPV hemagglutinin by two-dimensional 1H n.m.r. and methylation analysis.

The structures of the oligosaccharides of the hemagglutinin of fowl plague virus [influenza A/FPV/Rostock/34 (H7N1)] have been elucidated by one- and two-dimensional 1H n.m.r. spectroscopy at 500 MHz and by microscale methylation analysis. N-Glycosidic oligosaccharides of the oligomannosidic (OM) and of the N-acetyllactosaminic type have been found, the latter type comprising biantennary structures, without (A) or with (E) bisecting N-acetylglucosamine, and triantennary (C) structures. Analysis of the tryptic and thermolytic glycopeptides of the hemagglutinin allowed the allocation of these oligosaccharides to the individual glycosylation sites. Each attachment site contained a unique set of oligosaccharides. Asn12 contains predominantly structures C and E which are highly fucosylated. Asn28 contains OM and A structures that lack fucose and sulfate. Asn123 shows A that has incomplete antennae but is highly fucosylated and sulfated. Asn149 has fucosylated A and E. Asn231 shows fucosylated A and E with incomplete antennae. Asn406 has OM oligosaccharides. Asn478 has A and E with little fucose. Localization of the oligosaccharides on the three-dimensional structure of the hemagglutinin revealed that the oligomannosidic glycans are attached to glycosylation sites at which the enzymes responsible for carbohydrate processing do not have proper access. These observations demonstrate that an important structural determinant for the oligosaccharide side chains is the structure of the glycoprotein itself. In addition, evidence was obtained that the rate of glycoprotein synthesis also has an influence on carbohydrate structure.     

An estimate of unique DNA sequence heterozygosity in the human genome

Summary Patients with recessive X-linked ichthyosis Patients with recessive X-linked ichthyosis (RXLI), one hereditary form of scaly skin, lack activity of the enzyme steroid sulfatase in all tissues studied. To investigate the molecular defect underlying the lack of enzyme activity, we prepared antisera against normal enzyme by injecting normal placental microsomal suspensions or partially purified steroid sulfatase into rabbits. Antibody activity was assessed by immunoprecipitation of detergent solubilized steroid sulfatase. In addition, we prepared rabbit antisera against RXLI placental microsomal suspensions. To detect immunologically cross-reactive material in patients' placentas, extracts were studied by immunoblot techniques and by competition with normal enzyme for antibody binding. Patients' extracts did not contain immunoreactive material co-migrating on electrophoresis with purified enzyme nor did they inhibit immunoprecipitation of normal enzyme. Sera from rabbits immunized with RXLI placental microsomes contain no antibodies to normal steroid sulfatase, as judged by their failure to immunoprecipitate normal enzyme or to react with normal steroid sulfatase on immunoblot. Thus the mutation in RXLI appears to reduce steroid sulfatase enzyme protein as well as enzyme activity. Portions of this material have appeared in abstract form in Clinical Research 31:564A, 1983 and 32:138A, 1984     

Spike synchronization of tympanic receptor fibres in a grasshopper (Chorthippus biguttulus L., Acrididae)

In recordings from single tympanic receptor fibres in C. biguttulus, the response to synthesized sounds (rectangularly modulated white noise) interrupted by very brief (a few milliseconds) gaps was examined. In behavioral tests, females of the species respond very differently to such 'model syllables' at moderate intensities, depending on the gap width. If the gaps (in a moderate-intensity syllable) are larger than 2 ms, the stimulus fails to elicit a response, whereas stimuli with gaps smaller than 1 ms are as effective as uninterrupted syllables (D. von Helversen 1972; O. von Helversen 1979). Neither the mean spike count nor the interspike-interval distribution of the single receptor response contains the information sufficient to distinguish uninterrupted syllables from syllables with gaps. On the other hand, examination of the temporal distribution of the spikes reveals that gaps (or the pulse onsets following the gaps) cause spike synchronization. An index of synchronization (IS) was defined as a measure of this gap-induced effect. Analysis of the receptor responses based on IS revealed differences that correspond quantitatively to the abrupt abolition of the behavioral response at a gap-width between 1 and 2 ms. From the hypothesis that such brief gaps are detected by the nervous system by way of spike synchronization in the tympanic nerve, one can predict certain features of the behavioral response to high-intensity stimuli. The gap-induced spike synchronization was more pronounced at higher temperatures. This effect was demonstrated in both summated recordings from the tympanic nerve and single fibre recordings. Experiments with primary auditory fibres of Locusta migratoria showed that the receptors in this species respond very similarly to the same stimuli. That is, the receptors of C. biguttulus are not specially adapted for detecting very brief gaps. Synchronization of the spikes in parallel receptor fibres of the tympanal nerve is probably a general feature of acridids; we infer that in C. biguttulus this gap-induced synchronized activity is detected by special processing in higher auditory centres.     

Immuno-electron-microscopic evidence of ecdysteroids in Y-organ of Orconectes limosus (Crustacea,Decapoda)

Ecdysone was demonstrated by ultrastructural immunocytochemistry to be present in the mitochondria of the Y-organs of the crayfish Orconectes limosus. This is in remarkable contrast to the prothoracic glands of insects and suggests substantial differences in the biosynthesis of the same hormone, ecdysone, in crustaceans and insects.