Investigation of knot nests on Ellesmere Island

Knots arrive on Ellesmere Island in late May or early June. At Hazen Camp small flocks were present on 3 June 1966, but the main influx occurred 5 June when many flocks were seen ranging in size from 6 to 60 individuals. The sexes appeared to arrive together, but the manner of pair-formation was not determined. By 7 June pairs were distributed over the tundra with large feeding flocks forming at snowfree wet marshy areas. Most nests were on Dryas-hummocked slopes and tundra, either dry or moist, with some on clay plains and summits in a mixed Dryas and Salix vegetation. A census area of 240 ha supported at least 3 breeding pairs, and possibly 5; the total number of pairs breeding in the Hazen Camp study area was estimated to be about 25 (1.09 pairs/km**2). Egg-laying (4 nests) extended from 15 to 28 June, with 3 of the 4 sets completed between 20 and 23 June. Both sexes incubated, one of the pair more regularly than the other. The song-flight display of the male was performed most frequently during egglaying and incubation. The incubation period of the last egg in one clutch was established as being between 21.5 and 22.4 days. Four nests hatched between 12 and 20 July, and the hatching period of the entire clutch was less than 24 hours. Four of 7 nests (57 %) survived and egg survival (53 %) was low. Families left the nesting area so on after hatching, concentrating at ponds where food was readily available for the young. Both adults attended the young during the pre-fledging period, but the females apparently departed before the young had hedged. Males left once the young could fly and the adult fall migration was complete by early August. Most 01 the young departed belore mid-August. Fall migration is complete by late August or early September. The breeding season appears to be timed to peak load supply for the young. Adult Chironomidae emergence was highest between 3 and 17 July, the period during which most successful nests hatched. The increasing scarcity of adult insects for the young after mid-July was offset by family movements over the tundra and the early departure of half the adult population. Food also seemed to influence the distribution of breeding pairs aver the tundra, restricting them to the general vicinity of marshes, streams, and ponds where food is most available when the young hatch. Territoriality in the Knot appears to be closely associated with the protection of the nest against predators and has at least a local effect in regulating the number of breeding pairs. Plant material was important in the diet of adult Knots throughout the summer and the primary food from the time of arrival until mid-June. After mid-June the percentage of animal matter increased as dipterous insects became available (especially adult Chironomidae), but plant materials continued to constitute a large part of the diet, usually more than 50 %. The food of the young before fledging consisted principally of adult chironomids.

Experiment on marine fungus Microascus brevicaulis strain

The marine fungus Microascus brevicaulis strain LF580 is a non-model secondary metabolite producer with high yields of the two secondary metabolites scopularide A and B, which exhibit distinct activities against tumour cell lines. A mutant strain was obtained using UV mutagenesis, showing besides higher production levels faster growth and differences in pellet formation. Comparative proteomics were applied to gain deeper understanding of the regulation of production and of the physiology of this fungus and its mutant. For this purpose, an optimised protein extraction protocol was established. Here, we show the first proteome study of a marine fungus. In total, 4759 proteins were identified. The central metabolic pathway of LF580 could be mapped by using KEGG pathway analysis and GO annotation. Using iTRAQ labelling, 318 proteins were shown to be significantly regulated in the mutant strain: 189 were down- and 129 upregulated. Proteomics are a powerful tool for the understanding of regulatory aspects: The differences on proteome level could be attributed to a limited nutrient availability in wild type strain due to a strong pellet formation. This information can be applied to optimisation on strain and process level. The linkage between nutrient limitation and pellet formation in the non-model fungus M. brevicaulis is in consensus with the knowledge on model organisms like Aspergillus niger and Penicillium chrysogenum.

PaleoTools - extended software package for quantitative paleoenvironmental reconstructions

The Imbrie and Kipp transfer function method (IKM) and the modern analog technique (MAT) are accepted tools for quantitative paleoenvironmental reconstructions. However, no uncomplicated, flexible software has been available to apply these methods on modern computer devices. For this reason the software packages PaleoToolBox, MacTransfer, WinTransfer, MacMAT, and PanPlot have been developed. The PaleoToolBox package provides a flexible tool for the preprocessing of microfossil reference and downcore data as well as hydrographic reference parameters. It includes procedures to randomize the raw databases; to switch specific species in or out of the total species list; to establish individual ranking systems and their application on the reference and downcore databasessemi; and to convert the prepared databases into the file formats of IKM and MAT software for estimation of paleohydrographic parameters.