Settlement and juvenile habitat of the European spiny lobster <i>Palinurus elephas</i> (Crustacea: Decapoda: Palinuridae) in the western Mediterranean Sea

Abstract

SUMMARY: Settlement characteristics, like timing, depth, microhabitat and density of European spiny lobster Palinurus elephas are described for the very first time. Regular SCUBA-diving surveys were conducted from July 1998 to January 2000 on rocky bottoms of three different geologic origins to assess substratum-dependent differences in recruitment density. Settlement of pueruli took place in June-July, a few weeks after sea surface temperature started to rise. The highest density of juveniles was found at 10-15 m depth. Most spiny lobsters settled in limestone rocks, into empty holes of the date mussel Lithophaga lithophaga, which provided daytime refuge. As they grew, individuals were increasingly found in larger holes and crevices of the rock surface. Sizes were estimated from photographs taken at night when the animals were actively foraging. The smallest observed individuals measured 7.5-8 mm carapace length (CL), but they reached 15-18 mm CL at the end of October. The consequences of our results for the management of the spiny lobster populations in the northwestern Mediterranean are summarily discussed.

Differential catchability of male and female European spiny lobster Palinurus elephas (Fabricius, 1787) in traps and trammelnets

“…The maximum sizes (L ∞ ) of the male and female lobster caught during this study were slightly over the maximum sizes estimated by Marin (1987) (females L ∞ : 137 mm CL; males L ∞ : 168 mm CL). The scarcity of lobster smaller than 60 mm CL in survey catches may be explained by the shallow distribution and restricted home range of early juveniles (Díaz et al, 2001;Goñi et al, unpublished data). Additionally, in trap catches, small lobster may be underrepresented due to the selective properties of the gear and aggressive encounters with large conspecifics (Miller, 1990;Pezzack and Duggan, 1995).…”

Spillover of spiny lobsters Palinurus elephas from a marine reserve to an adjoining fishery

“…It inhabits rocky and coralligenous habitats from near shore to depths of 200 m; in the study area the species reaches maximum densities at depths of 60 to 90 m. It is a long-lived (maximum estimated age +15 yr), slow-growing species that reproduces once a year (Marin 1987). In the Western Mediterranean reproduction occurs from July to September, eggs hatch January to February (Goñi & Latrouite 2005), and post-larvae puerulus settle from June to September (Díaz et al 2001). Tagging studies conducted in the Atlantic and Mediterranean indicate that adult movement is restricted with most individuals moving less than 5 km, although there are 2 reports of recaptures 50 and 70 km away (Goñi & Latrouite 2005).…”

Spatial differences in size of maturity and reproductive potential between inshore and offshore fisheries for southern rock lobster (Jasus edwardsii) in South Australia

“…While the complexity of inshore reefs within South Australia is relatively well described (Lewis, 1981;Turner et al, 2007), offshore reefs are less well documented. The ability of habitat complexity to control the growth and subsequent size of maturity of crustaceans, has been described for numerous species including Homarus americanus (Cooper and Uzmann, 1980;Hudon, 1987), H. gammarus (Howard, 1980;Linnane et al, 2000), P. japonicus (Norman et al, 1994), P. ornatus (Skewes et al, 1997), and P. elephas (Díaz et al, 2001). Recent research in the SZ of South Australia indicates that shelter size is an important factor in determining localised lobster densities (M. Hoare, unpublished data).…”