© Baker, J.L. (2009) Marine Species of Conservation Concern in South Australia Full citation Baker, J.L. (2009) Marine Species of Conservation Concern in South Australia: Volume 1 - Bony and Cartilaginous Fishes. Report for the South Australian Working Group for Marine Species of Conservation Concern. J. Baker (consultant); Science and Conservation Division, and Coast and Marine Conservation branches of S.A. Department for Environment and Heritage (DEH); Marine and Coastal Community Network of S.A. (MCCN), and Threatened Species Network (TSN). Web version published by Reef Watch, South Australia.

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Black Rockcod / Saddled Rockcod / Black Cod / Spotted Black Grouper

Family Name:	Serranidae
Scientific Name:	Epinephelus daemelii (Günther, 1876)
Recommended Status in S.A:	Rare E(i) in S.A.; Vulnerable nationally; Should be protected under the S.A. Fisheries Management Act 2007
Rationale:  The species is included here because the Black Rockcod is known to occur in part of South Australia, as an expatriate from the eastern States. The species is considered to be vulnerable at a national scale, and most of the recovery objectives and management actions required to conserve populations of Black Rockcod rely upon action taken in the eastern States (particularly N.S.W. and Queensland), New Zealand, and other areas where the species is more prevalent (see recommended actions in Pogonoski et al. 2002). However, because the species is known to have significantly declined in other States and regions, protection in South Australian waters may, to a small extent, assist the national recovery efforts. In New South Wales, species at the end of the known range are often afforded formal protection under N.S.W. law (D. Pollard, pers. comm. 2002), and it may be appropriate that a similar strategy is used in South Australia.

Page Contents

Current Conservation Status

Listed under section 15 of the Commonwealth Fisheries Management Act 1991, making its take in fishing operations under that Act illegal unless covered by a scientific permit (Pogonoski, 2000). The national conservation overview for this species (Pogonoski et al., 2002) recommended listing of E. daemelii as a threatened species under the Commonwealth’s EPBC Act 1999. Between 2003 and 2006, E. daemelii was being assessed by the Commonwealth’s Threatened Species Scientific Committee, for listing as a threatened species under Commonwealth legislation (EPBC Act 1999). As at October 2008, the species had not yet been listed under the EPBC Act. 
Totally Protected Species in N.S.W. waters (since 1983), and listed as a Vulnerable species in N.S.W. under the Fisheries Management Act 1994 (Pogonoski, 2000).
Protected in New Zealand under the Wildlife Act 1953 (Schedule 7A) (Taylor et al., 1997), and a Totally Protected Species in the Kermadec Islands Marine Reserve (New Zealand)
ASFB Threatened Fishes Committee1988-1989: Requiring investigation of its status; 1990-1999: Potentially Threatened
Australian Society of Fish Biology 2001 list: Vulnerable
Pogonoski et al. (2002) suggested as conservation status: Vulnerable, on an Australia-wide basis.
In 2007, the species was listed on the IUCN Red List, as Near Threatened globally (IUCN, 2008).

Distribution

General

Epinephelus daemelii occurs in warm temperate and subtropical waters of the south-western Pacific: south-east Australia, Lord Howe Island, Norfolk Island, New Zealand, and Kermadec Islands (Paulin et al., 1989; Randall and Heemstra, 1991; Heemstra and Randall, 1993; Francis, 1993, 1996; Gomon et al., 1994; Francis et al., 1987; Pogonoski, 2000).
In New Zealand, E. daemelii is known from North Island and Poor Knights Islands, and there are scattered locations as far south as Westport in North-West South Island (Francis, 1996). This species is reported to be relatively abundant at the Kermadec Islands and the Three Kings Islands, but rare elsewhere in New Zealand (Francis, 1996, cited by Pogonoski et al., 2002).
Black Rockcod is considered to be the dominant Serranid at Elizabeth Reef and Middleton Reef (Gill and Reader, 1992, cited by Pogonoski et al., 2002), which are Marine National Nature Reserves in the Australian territory, and have also been designated as a Ramsar site (No. 1223). A survey at Elizabeth Reef in 2003 reported that the abundance (about 4 fish per ha.) had remained stable (neither increasing nor decreasing) since the previous survey in 1987 (Oxley et al., 2004).

Southern Australia

Notes from Pogonoski (2000) and Pogonoski et al., 2002): In Australia, the main part of the distribution is from southern Queensland to northern Victoria. The species has been reported from Bass Strait, but is not known from the coast of Tasmania (Heemstra and Randall, 1993). Parker (1999) reported adults to occur occasionally at Julian Rocks Aquatic Reserve (off Byron Bay) and at Windarra Bank (9nm east of Mooball, N of Cape Byron) in a depth range of 5-40m. Kuiter (1997) considered E. daemelii to be a common N.S.W. species. Johnson (uncited reference) noted that the northernmost confirmed and photographed record was a large specimen taken off Breaksea Spit (24^o15’S), Fraser Island in 1998.

South Australia

Rarely, the Black Rockcod has been found westwards to Kangaroo Island in South Australia (Gill and Reader, 1992; Heemstra and Randall, 1993, cited by Pogonoski et al., 2002), and these latter fish are considered to be expatriates from the east coast (Pogonoski et al., 2002). The South Australian extension of the distribution appears to be based upon a record held by the South Australian Museum (SAMA F 05430), being a specimen from Cape Bouguer, off southern Kangaroo Island.
According to Gomon et al. (1994), there is an undescribed species of Epinephelus known only from several specimens taken in offshore waters of South Australia, and this species, named “the Southern Rockcod”, resembles E. daemelii.

Habitat

Habitat notes from Pogonoski (2000), Pogonoski et al. (2002) and Kuiter (1996a and 1996b):
Epinephelus daemelii is a home-ranging species, and the adults are found in caves, gutters and beneath bomboras and ledges (Gill and Reader, 1992) on rocky reefs, from near shore to depths of at least 50m (Heemstra and Randall, 1993).
This species is generally found on coastal reefs, shallow rocky estuaries (darker individuals) and deeper offshore waters (often in caves), and is active at dusk and at night, thus is often not seen except when diving with a torch at night (Kuiter, 1996a and 1996b).
Recently settled juveniles can be common in coastal rock pools along the N.S.W. coastline (Hutchins and Swainston, 1986, cited by Pogonoski et al., 2002), and larger juveniles around rocky shores in estuaries (NSW Department of Primary Industries, 2005).

Notes on the Biology and Behaviour

Age and Growth

The Black Rockcod is a large species, and in Australian waters, E. daemelii attains at least 1.55m total length, and a weight of 81kg (Hutchins and Swainston, 1986; Leadbitter, 1992, cited by Pogonoski et al., 2002; Australian Museum, 2002j). Fish as large as 1.5m were recorded at Elizabeth Reef during a survey in 2003 (Oxley et al., 2004).
In New Zealand waters the maximum recorded size is 1.8m, but they are usually 40-80cm in length (Paulin and Roberts, 1992, cited by Pogonoski et al., 2002). At the Kermadec Islands, north of New Zealand, where the population has not been fished commercially, E. daemelii may reach 2m in length (Pogonoski, 2000; Pogonoski et al., 2002).
One of the largest specimens for which weight is recorded (81.64kg) was taken by spearfishing in N.S.W., in 1976 (Australian Underwater Federation, 2003). The maximum weight recorded by the Australian Anglers Association Records Authority is 57.5kg, being a specimen taken in New South Wales, in 1982 (Australian Anglers Association, 2005).
The species is slow-growing (Leadbitter, 1992, cited by Pogonoski, 2000, Pogonoski et al., 2002).

Behaviour

Epinephelus daemelii is a long-lived, slow-moving, aggressive, territorial species that may occupy a particular cave or ledge area for life (Heemstra and Randall, 1993, cited by Pogonoski, 2000; Pogonoski et al., 2002).
Observations by fishers and divers suggest that this species is slow-growing and it is also a slow- moving fish (Leadbitter, 1992, cited by Pogonoski et al., 2002).
Ayling and Cox (1982, cited by Pogonoski et al., 2002) noted of E. daemelii in New Zealand: “a single fish can change from one extreme of colour to the other in just a few seconds, depending on its mood and the colour of the background”. Black Rockcod is usually black in estuaries and banded around clear water reefs (N.S.W. Department of Primary Industries, 2005).

Reproduction

The Black Rockcod, like many groupers, is a protogynous hermaphrodite (Heemstra and Randall, 1993, cited by Pogonoski, 2000).
Small fish are females and change sex to become males at around 100-110cm length (Francis, 1996; Paulin and Roberts, 1992, cited by Pogonoski, 2000).
Epinephelus daemelii does not form breeding populations in the North Island waters of New Zealand, but individuals may grow to a large size and so appear to be capable of surviving for a number of years (Stewart, 1999, cited by Pogonoski, 2000, and Pogonoski et al., 2002). Their status in New Zealand mainland waters is not secure, as they do not form breeding populations (C. Roberts, pers. comm., cited by Pogonoski et al. 2002).

Diet and Feeding Behaviour

Epinephelus daemelii is an opportunistic carnivore (Leadbitter, 1992), which preys on fishes and crustaceans (McCulloch, 1922). Juveniles feed on small crabs and fishes (Heemstra and Randall, 1993, cited by Pogonoski, 2000 and Pogonoski et al., 2002). Sea urchins are also likely to be part of the diet (S. Shepherd, SARDI, pers. comm., 2006).

Other Information

Like many large groupers that govern a home territory, the Black Rockcod is likely to have a low abundance, especially as adults, and large males are considered to be rare (Pogonoski, 2000).

Fisheries Information

The species is caught as bycatch in Commonwealth fisheries (the Southern and Eastern Scalefish and Shark Fisheries - SESSF) (AFMA, 2002a), although it is illegal to take this species under Commonwealth law.
Although Black Rockcod has in the past been a valuable food fish, particularly in New South Wales (e.g. see summary in Pogonoski, 2000), there is now little targeted fishing for this species due to its vulnerable and protected status. The Black Rockcod is likely to be taken in small numbers by commercial and recreational fishing activities in rocky shore and island habitats, along the southern Queensland, N.S.W. and northern Victorian coastlines (Pogonoski, 2000).
Although capture of Black Rockcod is illegal in eastern Australia, a sports fishing web site recently included E. daemelii in the list of “prolific” fish species around Lord Howe Island, stating that accidental capture of this species was “inevitable”, despite its protected status (Lord Howe Island Sports and Gamefishing web site, 2004).
The species has been recorded as bycatch in rock lobster pots, on southern Kangaroo Island (Cape du Coeudic – Cape Bouguer area) (S.A. Museum record). Catch statistics in the South Australian Rock Lobster Fishery for all Serranids combined, are discussed above, in the section on Serranidae.

Vulnerable Characteristics of the Species

Black Rockcod is a large, long-lived, slow-growing, slow-moving, aggressively territorial species; that may occupy the same cave / reef for life (Heemstra and Randall, 1993, cited by Pogonoski et al., 2002; NSW Department of Primary Industries, 2005c). Like many large groupers, the species is inherently rare (with naturally low numbers of individuals); has a low natural mortality rate; is a protogynous hermaphrodite; may aggregate to spawn; and reaches maturity and maximum size slowly. The Black Rockcod is also curious by nature (and therefore attracted to divers and hooks), and it is a highly esteemed food fish. All of these characteristics make E. daemelii, particularly the larger individuals, extremely vulnerable to over-exploitation by spear-fishing, line fishing and (to a lesser extent) netting. In the past, populations in some areas of eastern Australia and New Zealand have been quickly reduced by recreational as well as commercial fishing (N.S.W. Fisheries Scientific Committee, undated, a; Australian Museum, 2002j; Pogonoski et al., 2002; NSW Department of Primary Industries, 2005c). The species has a low resilience to fishing pressure (N.S.W. Department of Primary Industries, 2004), and has long been over-fished in some areas. For example, the N.S.W. Independent Fisheries Scientific Committee reported that historical evidence (pre-1908) indicates that a decline in abundance, and possibly size, occurred around the turn of the century due to fishing pressure, especially near large towns or cities; and anecdotal evidence from the 1960’s and 1970’s (documented in various fishing magazines), indicated over-fishing by recreational line fishers and spear fishers, as large specimens of Black Rockcod were considered a prized catch. There is evidence that although the species is now protected in N.S.W., fish are still suffering mortality due to hooks from fishers (N.S.W. Fisheries, 2003g).
Furthermore, the species changes sex from female to male at around 100 - 110cm (Paulin and Roberts, 1992, cited by Pogonoski et al., 2002), and the resultant exploitation of certain size/age classes may thus affect the population dynamics of the species, through imbalance to the sex ratio of populations in exploited areas. Species which are protogynous hermaphrodites tend to have sex ratios that are naturally biased towards females, but this bias can be artificially increased by selective fishing of the larger fish (males) (Coleman et al., 2000). This feature of the life history makes such species particularly susceptible to over-fishing, because the loss of large males through selective fishing may limit the reproductive success of the population, especially where fishers target spawning aggregations (Coleman et al., 2000). This effect may be reduced if the transition of large females to males occurs rapidly enough to compensate for the loss of males, but it is not known whether such compensation can occur for Black Rockcod, or whether the species has spawning aggregations (N.S.W. Department of Primary Industries, 2004).
There is some evidence that fish caught in deeper (50-100m) waters by commercial fishers do not survive after being released at the surface, suffering severely from swim-bladder decompression or “bloat” (Pogonoski et al., 2002).
Like many large groupers that govern a home territory, the Black Rockcod is likely to have a low abundance, especially as adults, and large males are considered to be rare (Pogonoski, 2000).
The species is reported to have a very low resilience to exploitation, in terms of population doubling time (Froese and Pauly, 2006).
In 2003, the Fisheries Scientific Committee of New South Wales Fisheries proposed the nomination of hook and line fishing as a Key Threatening Process (under Schedule 6 of the Commonwealth’s Environment and Biodiversity Act, 1999), in areas important for the survival of threatened fish species, such as E. daemelii (N.S.W. Fisheries, 2003g).

Threatening Processes

Historically and currently, fishing is the main threatening process. Notes from Pogonoski (2000) and Pogonoski et al. (2002) on previous decline in populations due to fishing: Roughley (1916) reported of E. daemelii “at one time it was fairly plentiful in the vicinity of Port Jackson, but has become very scarce in recent years, owing to the havoc wrought by fishermen, and the increased shipping”. McCulloch (1922) reported that E. daemelii was a valuable food fish in N.S.W., indicating that this species was once quite common in that state. The total fishing ban in N.S.W. was enforced following a noticeable decline in numbers, mainly attributed to the rise in the popularity of spearfishing in the early 1970's (Leadbitter, 1992). Lincoln-Smith et al. (1989) noted that in N.S.W., 137 Black Rockcod averaging 2.4kg per fish were speared in N.S.W. spearfishing competitions in 1976 alone (Pogonoski, 2000; Pogonoski et al., 2002).
In N.S.W., the decline in E. daemelii populations was evident by the mid 20th century (1950s – 60s) (S. Shepherd, pers. comm., 2006). The declining numbers of Black Rockcod due to commercial and recreational fishing (including spear-fishing during the 1970s) resulted in the species being declared protected in New South Wales waters in 1983 (Australian Museum, 2002j). However, although Black Rockcod is now protected in NSW, the species has shown no significant recovery since it was first protected under legislation (N.S.W. Fisheries Scientific Committee, undated).
The main threat to this species appears to be illegal fishing, and an additional threat is posed by commercial and recreational fishing activities in which the species is taken as bycatch, from rocky shores and island habitats along the southern Queensland, N.S.W. and northern Victorian coastlines (Pogonoski, 2000). The species is an aggressive feeder that readily takes a hook (Bohm, 2003), and therefore hooking injuries of accidentally caught fish may be an additional threat to the illegal fishing (NSW Department of Primary Industries, 2005c). Although the Black Rockcod is protected in New South Wales, many recreational fishers may not be able to readily identify this species (Bohm, 2003). Given the increases in fishing technology during the past two decades, recreational fishers now have the capacity to move further offshore, and to target fish on specific reefs that were previous “refuges” for large, site-associated species such as Black Rockcod.    
Habitat disturbance may also be a threat to populations (National Oceans Office, 2002). For example, impacts on juvenile black cod may occur due to the loss or degradation of estuarine nursery habitats (NSW Department of Primary Industries, 2005b).
Alteration of predator-prey relationships is also reported to be a threat to Black Rockcod populations (National Oceans Office, 2002).

Research Requirements

Due to the existence of limited biological information, Pogonoski et al. (2002) recommended further studies on the biology of Black Rockcod, including the use by museums or research institutions, of specimens that occasionally appear at markets in the eastern States. Information on age/size classes, the age/size at maturity, sex ratios and fecundity levels are required, to determine, amongst other things, the proportion of mature adults in a given population. Research is now being undertaken in this area (see section below). Pogonoski et al. (2002) also recommended the formation of a National Recovery Team to accumulate information on the distribution, abundance, exploitation, biology (e.g. age and size at maturity, fecundity, home range, etc.) and ecology (e.g. specific habitat preferences, diet etc) of Black Rockcod.
The diet of this large carnivore is barely documented. It is quite possible Black Rockcod, being a large carnivorous fish species, might eat sea urchins (as does Blue Groper). According to S. Shepherd (pers. comm., 2006) it is possible that the demise of Black Rockcod in N.S.W. during the mid 20^th century was partly responsible for the increase in numbers of sea urchins, and the consequent development of “barrens”.
The taxonomic identity of the “Southern Rockcod” in South Australia should be ascertained, including its relationship with E. daemelii. Research needs to determine whether there are populations of Black Rockcod and the “Southern Rockcod” in S.A., or whether the presence is restricted to “expatriates” from south-eastern Australia.
Rock lobster fisheries bycatch should be monitored over space and time in off Kangaroo Island and the south-east of South Australia, for the presence of E. daemelii, and the related “Southern Rockcod”.

Research Notes

In N.S.W., recent research projects aim to (i) increase knowledge of the distribution, biology and ecology of the species, and (ii) determine areas that could be considered critical habitat (NSW Department of Primary Industries, 2005b and 2005c).
Between 2005 and 2007, the University of Technology in Sydney received a grant to investigate the conservation ecology of Epinephelus daemelii, in conjunction with NSW Fisheries. Although the Black Rockcod is listed as vulnerable in N.S.W., very little more is known about the species today than over 20 years ago, when E. daemelii was first protected. Given that, the project aims to increase the effectiveness of Black Rockcod management by determining the distribution, abundance, stock structure, fecundity, spawning behaviour and recruitment. The project also aims to provide information that is relevant to a recovery plan, and a review (internationally and nationally) of the status of Black Rockcod (Australian Research Council, 2005).
As E. daemelii inhabits rocky reef areas with caves and gutters, it may be afforded some protection by Marine Protected Areas in N.S.W. that are designed to protect the Grey Nurse Shark (Pogonoski et al., 2002). A study by Sydney’s University of Technology (see above) is collaborating with the NSW Fisheries’ Grey Nurse Shark program, to assess the importance of Grey Nurse Shark Critical Habitat areas in maintaining Black Cod populations.

Management Requirements

In the eastern States, educating commercial and recreational fishers of the anatomical and visual characteristics that distinguish the Black Rockcod from other similar looking closely related cod species is considered essential for its continued protection and survival in Australian waters (Pogonoski et al., 2002).
Commercial fishers in N.S.W. waters should record interactions with this species to help accumulate information on distribution and threats (Pogonoski et al., 2002).
In recreational fishing surveys, the accidental catch of Black Rockcod should be recorded at species level, rather than all groupers being aggregated into a single category (as occurred with the National Recreational and Indigenous fishing Survey in 2000-01, from which it was not possible to determine how many Black Rockcods were caught incidentally in any State).
Populations of strongly site-associated reef fish species such as E. daemelii can be better protected by the designation of marine reserves / harvest refugia and other no-take fishing zones (Pollard, 1993; Pogonoski et al., 2002). The implementation of Marine Protected Areas or no-take fishing zones in known habitats may be necessary, in addition to the protection offered by fishing bans in N.S.W. and Commonwealth waters (Pogonoski, 2000). It is noted that recent protection in parts of New Zealand (e.g. the Kermadec Islands) may help to reduce the over-exploitation of the large, easily approached Black Rockcod individuals (Stewart, 1999, cited by Pogonoski, 2000).

Management Notes

In the Commonwealth-managed Southern and Eastern Scalefish and Shark Fisheries (SESSF), the capture and landing of Black Rockcod is prohibited in waters off all the southern States (N.S.W., Tasmania, Victoria, S.A. and W.A.) (AFMA, 2004e, 2005b).
In New South Wales, the various measures being undertaken to ensure the recovery of Black Rockcod populations include the following: (i) maintaining bans on taking of the species in NSW and Commonwealth waters, and encouraging similar measures in Queensland; (ii) educating fishers about how to identify Black Rockcod, and the best ways to return any incidentally caught specimens to the water; (iii) protecting Black Rockcod from illegal fishing (where possible); (iv) conserving and promoting the restoration of estuarine nursery habitats; and (v) implementing the Protected, Threatened and Pest Species Sighting Program (see below), to improve knowledge of the distribution and abundance of the species (NSW Department of Primary Industries, 2005b,c)
NSW Department of Primary Industries (2005c) has produced a guide for fishers and divers, on protecting Black Rockcod. The guide contains information about identifying the species, protecting its habitats, dive protocols, and tips for fishers, about safely returning accidentally caught specimens to the water.
According to the NSW Department of Primary Industries (2005c), the 10 protected areas known as Grey Nurse Shark Critical Habitats, also provide protection for Black Rockcod populations and their habitats. A number of marine parks and reserves are also listed as assisting in the protection of Black Rockcod, including Cook Island Aquatic Reserve, Solitary Islands Marine Park, Jervis Bay Marine Park, Cape Byron Marine Park, and Lord Howe Island Marine Park. It is noted that although Black Rockcod is fully protected in N.S.W., fishing is not prohibited in all parts of marine parks, and accidental catch and mortality of Black Rockcod may be possible.  
NSW Fisheries has a Protected and Threatened Species Sighting Program, and fishers who see or accidentally catch a Black Rockcod are encouraged record the details, including date, exact location, depth of water; and estimated size of fish.
Given the protected status of E. daemelii in N.S.W., it is considered in the environmental impact assessments of coastal and marine developments, and State and local council levels. 
E. daemelii is one of the fish species monitored by community volunteers in N.S.W., as part of the HarbourKeepers and CoastKeepers programs, in association with the marine sector of the National Parks Association of NSW (CoastKeepers, 2006). 

Other Information

Illegal removal of E. daemelii from N.S.W. and Commonwealth waters is considered harmful to the survival of this species in Australian waters (Pogonoski et al., 2002). Continual protection in N.S.W. waters is considered crucial to the survival of E. daemelii along the Australian mainland coastline, because N.S.W. provides the largest area of the Black Rockcod’s distributional range in Australia (Pogonoski et al., 2002).
The status of the Black Rock Cod in New Zealand mainland waters is not considered to be secure, because the species does not form breeding populations there (C. Roberts, Museum of New Zealand, pers. comm. to J. Pogonoski, cited by Pogonoski, 2000).
The Black Rockcod is found in a number of protected reserves in and around New Zealand, such as the Poor Knight Islands (Denny et al., 2003) and the Kermadec Islands, where divers and dive charters visit for fish-viewing, and “interactions” with gropers.

Support for S.A. Listing:

Graham Edgar (University of Tasmania) recommended that Black Rockcod definitely be listed as a threatened species if present in S.A., and Barry Hutchins (ex-WA Museum) recommended Data Deficient category.