Variation in Dispersal of Galjoen (Coracinus capensis) (Teleostei: Coracinidae) from a Marine Reserve

Abstract

The dispersal of the surf-zone teleost galjoen (Coracinus capensis) from the De Hoop Marine Reserve, South Africa, was investigated. Over a period of 5.5 yr, 11 022 galjoen were tagged in the centre of the reserve. Most of the 1008 recoveries were at the site of release, while the remainder covered a distance of up to 1040 km. There was no difference with respect to age, sex, or season between those that dispersed and those that did not. Six models were developed to test the hypotheses that (1) galjoen are polymorphic with respect to dispersal behaviour, (2) nonreporting of tags masks a random dispersal process, and (3) the recovery distribution is the result of unequal movement rates in different areas. It is inferred from the likelihoods of the various models that the tagged population was polymorphic, with fish displaying either resident or nomadic behaviour. This conclusion is unaffected by a large uncertainty in the extent of nonreporting of recoveries, or by spatial variability of movement rates. The estimate of emigration from the reserve implies that the unharvested reserve population is restocking adjacent exploited areas with adult fish.

Evidence for long‐term site fidelity of snapper(Pagrus auratus)within a marine reserve

“…Snapper appear to conform to the "polymorphic behaviour" model of Attwood & Bennett (1994), in the sense that some individuals become resident on reefs, whereas others disperse over a wide area (Paul 1967;Crossland 1976Crossland , 1982Tong 1978). Many models (especially fisheries models) of fish population dynamics tend to be oversimplified, with particular documented behaviours attributed to entire species (where behaviour is considered at all).…”

Alternate explanations of the dispersal pattern of galjoenDichistius capensis

“…Galjoen swim in small groups and large shoals (Rust and Rust 2000), display resident behaviour and undertake large, unpredictable migrations (Attwood and Bennett 1994). The study of movement behaviour of fish has a strong applied value, because such behaviour will influence the effectiveness of marine protected areas as a mechanism of fish conservation, and it may affect the design of fishery monitoring programmes.…”

Do marine reserves export adult fish biomass? Evidence from Apo Island, central Philippines

“…In addition, a reasonable number of studies have specifically tried to demonstrate movement of target species from marine reserves to fished areas using tag-recapture technlques, e.g. lobsters (Davis & Dodrill 1980, shrimps (Gitschlag 1986), snow crabs (Yamasaki & Kuwahara 1990) and reef fish (Beinssen 1989, BI-yant et al 1989, Buxton & Allen 1989, Rutherford et al 1989, Holland et al 1993, Attwood & Bennet 1994, Davles 1995 In add~tion, several studies have modeled the potential effects of movemen.ts of adult fish from marine reserve to fished areas on yield per recrult of target species (Polacheck 1990, Russ et al 1992, DeMai-tlni 1993 The establishment of a no-fishing sanctuary that covered 2%) of the fishing ground for snow crabs in Japan led to a 46% increase in mean catch per unit effort in areas adjacent to the sanctuary after 5 yr of sanctuary protection (Yamasaki & Kuwahara 1990). This increase in catch rate was reported to be most evident within 3 miles (ca 5 km) of the boundary of the sanctuary.…”

“…Several studies have used tag-recapture techniques to estimate the amount of movement of reef fish from reserve to non-reserve areas (Beinssen 1989, Buxton & Allen 1989, Holland et al 1993, Attwood & Bennet 1994, Davies 1995. This subject was reviewed recently by Roberts & Polunin (1991) and Robertson (1988).…”

“…Several studies have used tag-recapture techniques a n d reported movements of target species from reserve to fished areas, e.g. lobsters (Davis & Dodnll 1980, shrimps (Gitschlag 19861, snow crabs (Yamasaki & Kuwahara 1990) and reef fish (Beinssen 1989, Bryant et al 1989, Rutherford et al 1989, Attwood & Bennet 1994, Davies 1995. In addition, studies have modeled the potential effects of movements of adult fish from marine reserve to fished areas on yleld per recruit of target species (Polacheck 2990, Russ et al 1992, DeMartini 1993 and suggested that such fisheries enhancement effects may b e possible under certain conditions.…”