Genetic diversity of isolated populations of Nautilus pompilius (Mollusca, Cephalopoda) in the Great Barrier Reef and Coral Sea

Abstract

Nautilus species are the only remaining cephalopods with an external shell.

The contribution of molecular data to our understanding of cephalopod evolution and systematics: a review

“…Studies have confirmed the validity of the genus Allonautilus and its sister-taxon relationship with Nautilus (Bonacum et al 2011). However, they have also suggested that Nautilus pompilius comprises many evolutionarily independent lineages and there are in fact many more species present in the Indo Pacific than are currently recognized (Sinclair et al 2007(Sinclair et al , 2011Bonacum et al 2011;Williams et al 2012). These are important data because of the susceptibility of Nautilus populations to intense fishery activity (Dunstan et al 2010).…”

Nautilus pompilius fishing and population decline in the Philippines: A comparison with an unexploited Australian Nautilus population

“…Past studies show Nautilus to be a series of genetically different populations which are separated geographically by ocean depths >800 m (Bonnaud et al, 2004;Saunders and Landman, 2010;Sinclair et al, 2007;Strugnell et al, 2006;Wray et al, 1995). The Palawan area affords a contiguous habitat for a single Nautilus population and shows the expected similar catch declines over all fishing locations around the island.…”

“…The geographical isolation of genetically distinct Nautilus populations (Sinclair et al, 2007;Woodruff et al, 1983;Wray et al, 1995) precludes, or drastically slows, recolonisation of depleted sub-populations and supports a strong argument for protection of all Nautilus stocks to maintain the genetic diversity necessary to allow survival of this living fossil. Close similarities in biology and ecology of other Nautilus species (Saunders, 1981b;Saunders and Landman, 2010;Sinclair et al, 2007;Strugnell et al, 2006;Ward and Saunders, 1997;Wray et al, 1995) argues for the inclusion of all members of this group in any management decisions.…”

“…Close similarities in biology and ecology of other Nautilus species (Saunders, 1981b;Saunders and Landman, 2010;Sinclair et al, 2007;Strugnell et al, 2006;Ward and Saunders, 1997;Wray et al, 1995) argues for the inclusion of all members of this group in any management decisions. All current evidence suggests the life history of slow growth, long life, low fecundity and restricted dispersal and recruitment are features of all Nautilus and Allonautilus species (Saunders, 1981a;Saunders et al, 1989;Saunders and Spinosa, 1979;Saunders and Ward, 1987;Sinclair et al, 2007;Tanabe et al, 1990;Ward, 2008;Ward and Saunders, 1997). The shells of N. pompilius, N. macromphalus and A. scrobiculatus are all marketed and sold by the international shell trade.…”

“…Nautiloids and their extinct predecessors have been a feature of the earth's oceans for over 500 million years and survived almost unchanged through five major mass extinction events (Hanlon and Messenger, 1996;Strugnell and Lindgren, 2007;Ward, 1980). Now only two to five species of Nautilus (taxonomy remains uncertain) (Bonnaud et al, 2004;Saunders, 1981b;Saunders and Landman, 2010;Sinclair et al, 2007;Wray et al, 1995) and one separate genus, Allonautilus (Ward and Saunders, 1997) represent the nautiloids in a distribution restricted to deep-water tropical habitats of the Indo-Pacific. Their k-selected life history traits of low fecundity, late maturity and long life span (Cochran et al, 1981;Saunders, 1983;Shigeno et al, 2008;Uchiyama and Tanabe, 1996;Westermann et al, 2004) lead to the vulnerability of Nautilus to overfishing, which is a major threat to their continued survival.…”