Melville-Smith and de Lestang; Changes in egg production of Ponulirus cygnus associated with appendage damage 419 



tralia is divided into three management zones: 

 the Abrolhos Islands (zone A), north coastal 

 (zone B), and south coastal (zone C) (Fig. 1). In 

 some cases data were pooled into these zones 

 for analysis. 



The surveys were undertaken over the course 

 of ten days before the start of the commercial 

 lobster fishing season on 15 November. This 

 period is very close to the annual peak of the 

 egg-bearing season, which is considered to oc- 

 cur in November of each year (Chubb, 1991). 

 Because this survey was designed to be re- 

 peatable, the same fishing gear (batten pots 

 with closed escape gaps), bait (a combination 

 of north sea herring [Clupea harengus] and 

 Australian salmon [Arripis truttaceiis]), and 

 locations (same GPS coordinates) were used. 

 The results are therefore directly comparable 

 between years. For more details on the survey 

 sampling regime see Chubb (2000). 



Measurements and records 



During the surveys, the carapace length (CL) 

 of each lobster was measured to the nearest 1 

 mm from midpoint between the preorbital spines 

 down the mid-dorsal line to the posterior edge 

 of its carapace. The presence of gonopores on 

 the base of the fifth pair of pereiopods was used 

 to identify males. For females, the presence of 

 ovigerous setae attached to the endopodites, the 

 visual appearance of the ovaries through the 

 dorsothoracic musculature, the presence and 

 developmental stage of external ova attached to 

 the setae, and the presence of a spermatophoric 

 mass attached to the fifth abdominal segment 

 were recorded. These data have been used to 

 predict whether a female would produce one or 

 two batches of eggs in a spawning season (such 

 females are known as "single breeders" and 

 "double breeders, respectively)" — see Melville- 

 Smith and de Lestang (2005) for a full descrip- 

 tion of this method). 



Loss and regeneration of antennae and limbs 

 were also recorded during the survey as ei- 

 ther an old loss, new loss, or as a regenerated append- 

 age and all three categories were grouped collectively 

 and referred to as "appendage damage." Old loss was 

 identified by dark melanization at the site of the lost 

 appendage and new loss by exposed flesh without mela- 

 nization. Although new leg losses were recorded, nearly 

 all were considered to have resulted from capture and 

 handling during the survey and therefore were ex- 

 cluded from our analysis of the impact of appendage 

 damage on reproductive output. Regenerated limbs 

 of P. cygtiiis were only easily identifiable in the first 

 intermoult period after the limb was lost and were 

 distinguished by being greenish in color and notice- 

 ably smaller or thinner than existing limbs. Because 

 old and new losses have been recorded since 1992 and 



113°E 114'E 115E 116E 117^E 118'E 



Kalbarri 



Abrolhos Islands 

 (zone A) 



Northern coastal (zone B) 



Oongara 



Jurien Bay 



L.ancelin 



Southern coastal (zone C) 



Fremantle 



Indian Ocean 



3rs 



34°S 



35°S 



Figure 1 



Management zones (zone A, Abrolhos Islands; zone B, northern 

 coastal; zone C, southern coastal) in the western rock lobster 

 iPanulirus cygnus) fishery, and six sites (five on the coast of West- 

 ern Australia and one comprising the Abrolhos Islands) used 

 for fishery-independent breeding stock surveys and commercial 

 monitoring of the catch. 



regenerated limbs have been recorded since 2001, we 

 used only the data collected since the 2001 survey. The 

 incidence of old losses, new losses, and regenerated 

 appendages between zones, sex, and carapace size was 

 compared by using ANOVA. 



Effect of appendage damage on fecundity estimates 



Because most of the lobsters sampled in zone A (the 

 Abrolhos Islands) during the 2001-03 surveys were 

 larger than the size at maturity (Melville- Smith and 

 de Lestang, 2006), data derived from sampling in this 

 location were used to examine whether the incidence of 

 old appendage-losses and regenerated appendages affects 

 the reproductive state of female P. cygnus. 



