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The article presents the study which examined the establishment of Escherichia coli in the endangered Australian sea lion (Neophoca cinerea), as well as the relationship between E. coli presence and phylotype distribution. In the study, the fecal samples from wild and captive sea lions were compared using molecular screening and gene cassette array sequencing.

Giardia and Cryptosporidium are amongst the most common protozoan parasites identified as causing enteric disease in pinnipeds. A number of Giardia assemblages and Cryptosporidium species and genotypes are common in humans and terrestrial mammals and have also been identified in marine mammals. To investigate the occurrence of these parasites in an endangered marine mammal, the Australian sea lion ( Neophoca cinerea ), genomic DNA was extracted from faecal samples collected from wild populations ( n  = 271) in Southern and Western Australia and three Australian captive populations ( n  = 19). These were screened using PCR targeting the 18S rRNA of Giardia and Cryptosporidium. Giardia duodenalis was detected in 28 wild sea lions and in seven captive individuals. Successful sequencing of the 18S rRNA gene assigned 27 Giardia isolates to assemblage B and one to assemblage A, both assemblages commonly found in humans. Subsequent screening at the gdh and β-giardin loci resulted in amplification of only one of the 35 18S rRNA positive samples at the β-giardin locus. Sequencing at the β-giardin locus assigned the assemblage B 18S rRNA confirmed isolate to assemblage AI. The geographic distribution of sea lion populations sampled in relation to human settlements indicated that Giardia presence in sea lions was highest in populations less than 25 km from humans. Cryptosporidium was not detected by PCR screening in either wild colonies or captive sea lion populations. These data suggest that the presence of G. duodenalis in the endangered Australian sea lion is likely the result of dispersal from human sources. Multilocus molecular analyses are essential for the determination of G. duodenalis assemblages and subsequent inferences on transmission routes to endangered marine mammal populations. [ABSTRACT FROM AUTHOR]

Discusses a research on the effects of climate change on the distribution of species. Percentage of species that will be committed to extinction by 2050; Discussion of the results of the research.