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Abstract: Amphibian defensive skin secretions are known to contain a plethora of biologically-active peptides that are often structural and functional analogues of vertebrate neuropeptides. Here we report the structures of two invertebrate neuropeptide analogues, IPPQFMRF amide (IF-8 amide) and EGDEDEFLRF amide (EF-10 amide), from the defensive skin secretions of two different species of African hyperoliid frogs, Kassina maculata and Phylictimantis verrucosus, respectively. These represent the first canonical FMRF amide-related peptides (FaRPs) from a vertebrate source. The cDNA encoding IF-8 amide was cloned from a skin secretion library and found to contain a single copy of the peptide located at the C-terminus of a 58 amino acid residue open-reading frame. These data extend the potential targets of the defensive arsenal of amphibian tegumental secretions to parasitic/predatory invertebrates and the novel peptides described may represent the first vertebrate peptidic endectocides. [Copyright &y& Elsevier]

Presents a study which investigate the effect which mobbing birds have on powerful owls, Ninox strenua, focusing on patterns of owl predation on mobbing and non-mobbing birds. Number of species which mobbed owls; Overview of mobbing behavior among birds; identification of mobbing birds.

Ephemeral gilgai wetlands of the stony-plains of arid Australia have a relatively high diversity of native plant species and are extensively utilised for livestock grazing. We sampled the standing vegetation (SV) and germinable soil seed bank (SSB) of 40 gilgais, comparing gilgais near and far from watering points, and continually stocked versus rarely stocked. Despite historically heavy stock grazing, we found no significant differences in native species richness between treatments, indicating the general resilience of gilgai vegetation. One contributing factor is the abundance of Atriplex nummularia ssp. omissa . Cover of this long-lived shrub did not differ significantly between treatments and was positively correlated with “highly palatable” species’ cover, suggesting that it may act as a nurse species. In contrast, two other long-lived species, Atriplex vesicaria and Astrebla pectinata , had significantly reduced cover or were absent near to watering points. These and other long-lived species had a poorly developed SSB and thus limited ability to regenerate from seed if killed by sustained heavy grazing. The absence of fifteen locally rare species (including 12 short-lived species) from water-near gilgais indicates the need for more intensive survey to determine whether the proliferation of watering points poses a threat to such species. [ABSTRACT FROM AUTHOR]