Isolated populations of freshwater crocodiles (Crocodylus johnstoni) in elevated, rocky escarpment areas of the Northern Territory reach sexual maturity earlier and generally have an adult size half that of their downstream counterparts. There is debate over whether these ‘pygmy’ or ‘dwarf’ crocodile populations are the result of extreme phenotypic plasticity or the origins of a unique species through peripatric speciation. This debate is of conservation concern as these populations face immediate threats of invasive species and climate change, and species classification can affect conservation management strategies. We used mitochondrial DNA control region and cytochrome b sequences to investigate whether mtDNA haplotype variation supports any evidence of speciation between the pygmy and standard-size freshwater crocodiles. Additionally, we used genotyping by sequencing (dd-RADseq) to examine genetic clustering. Separated and concatenated control region and cytochrome b haplotypes were shared between pygmy and standard-size crocodile populations. Principle Component Analysis and STRUCTURE analyses on dd-RADseq data showed pygmy and standard-size crocodiles cluster by geographic location as much as by phenotype. We found no clear and objective genetic evidence to suggest that the pygmy freshwater crocodiles should be considered a separate species to any other population of the standard-size crocodiles. However, the isolation and environmental adaptability of these unique pygmy freshwater crocodile populations make them ecologically unique and valuable for conservation, and worth safeguarding against potential threats.

Opportunistic observation of Erabu sea snakes (Laticauda semifaciata) provide evidence that these species undertake a novel foraging tactic; coordinated communal hunting. Erabu sea snakes prey on cryptic fish species in highly complex reef habitats. Intra- and interspecific cooperative hunting strategies may increase chances for all members of the hunting party to encounter and capture prey in these complex habitats. Here we recorded 52 instances of communal hunting by Erabu sea snakes with conspecifics and other predatory fishes at recreational dive sites in Southern Lombok, Indonesia. These observations highlight the potential higher cognitive capacity of sea snakes to coordinate activities around communal hunting events.