Population biology of the ghost shrimps, Trypaea australiensis and Biffarius arenosus (Decapoda: Thalassinidea), in Western Port, Victoria

Abstract

This study compared the population biology of two co-existing species of ghost shrimps, Trypaea australiensis Dana 1952 and Biffarius arenosus (Poore 1975), over a two year period at Warneet and Crib Point in Western Port, Victoria, south-eastern Australia. Overall, the sex ratio in populations of T. australiensis varied considerably (male and female biases were found at different times) whereas the sex ratio of B. arenosus was generally 1:1 or female biased. A male biased sex ratio was found in the juvenile size class of populations of T. australiensis (both years) and B. arenosus (one year only). Both species reproduced in spring and summer in Western Port and juveniles appeared to recruit into the populations all year round. The embryo and clutch size of T. australiensis females was signifi cantly larger than B. arenosus, and a signifi cant relationship between female body size and clutch size (but not embryo size) was found for both species. Comparisons between this and other population studies of T. australiensis and B. arenosus were made to highlight any latitudinal variation in the reproduction and breeding biology of these species along the eastern coast of Australia.

Reproductive biology and population structure ofAxianassa australis(Crustacea, Axianassidae) on a sand-mud flat in north-eastern Brazil

“…In thalassinidean crustaceans, the sex ratio can vary among species (see Hill, 1977 and Hanekom & Erasmus, 1989) or within species (among size classes or seasons of the year) (Berkenbusch & Rowden, 2000; Rotherham & West, 2009). Variations in the sex ratio have also been attributed to other stochastic factors such as differential mortality between sexes (loss of males due to fights for females), migration, predation (Felder & Lovett, 1989; Dumbauld et al , 1996), and bias imposed by sampling gear (Rowden & Jones, 1994; Botter-Carvalho et al , 2007; Butler et al , 2009). Although the general pattern for thalassinideans is equality for the overall population, among adult individuals, female dominance is common (Tunberg, 1986; Felder & Lovett, 1989; Dumbauld et al , 1996; Tamaki et al , 1997; Pezzuto, 1998; Shimoda et al , 2005; Botter-Carvalho et al , 2007) and the competition among males for females appears to be the driving force for this dominance (Felder & Lovett, 1989).…”

“…Dworschak, 1988, for Upogebia pusilla ; Hanekom & Baird, 1992, for U. africana ) and Axiidea (e.g. Berkenbusch & Rowden, 1998, for Callianassa filholi ; Shimizu, 1997 and Botter-Carvalho et al , 2007, for Callichirus major ; Dumbauld et al , 1996, for Neotrypaea californiensis ; Hernáez & Wehrtmann, 2007, for Callichirus seilacheri ; and Butler et al , 2009, for Trypaea australiensis and Biffarius arenosus .…”

A new species of Arenallianassa (Decapoda: Axiidea: Callianassidae) from hydrothermal vents with notes on its ecology and a redescription of Arenallianassa arenosa (Poore, 1975)

“…Scale bars = 2 mm. al., 1997;Bird and Poore, 1999;Bird, 2000;Stapleton et al, 2001;Bird, 2007, 2008;Butler et al, 2009), mostly incorrectly treated as a species of Biffarius Manning and Felder, 1991. Collections in Museums Victoria and the Australian Museum contain hundreds of specimens, mostly from intertidal or shallow beaches or mudflats close to Sydney and Melbourne, of which a few were re-examined here. The record from Gove, Northern Territory, is exceptional; otherwise, the northern-most record is from central Queensland.…”

“…Since these revisionary studies, an undescribed species belonging to Arenallianassa has been collected from two disjunct localities along the Kermadec-Tonga Volcanic Arc system. Interestingly, the new species was in both cases collected around shallow (~100-200 m depth) hydrothermal vents, an environment very different from its congener, A. arenosa, which is abundant in the intertidal and shallow waters of eastern Australia (Poore, 1975;Butler et al 2009).…”

Bioturbator‐stimulated loss of seagrass sediment carbon stocks

“…T. australiensis (henceforth referred to as "Callianassids") is an upward conveyor deposit-feeding bioturbator (Butler et al 2009;Kristensen et al 2012), that constructs complex burrows (typically with two openings; Katrak and Bird 2003) ranging from <10 cm (Butler and Bird 2008) to approximately 50 cm in depth (Stapleton et al 2001). Callianassids typically live on a diet of diatoms and small particles of organic material, preferring particles <63 μm in size (Stapleton et al 2001).…”