Daryl McPhee

Now that the various Covid regulations are over, I have been out and about doing community talks again. For those around Redcliffe and northern Brisbane, I have one coming up next month. 

Here is a summary some published information from a colleague Dr Barry Pollock. 

The annual spawning aggregation of dusky flathead 'Platycephalus fuscus' at Jumpinpin, Queensland

Dusky flathead 'Platycephalus fuscus' form seasonal spawning aggregations where estuaries meet the ocean in eastern Australia. The present study at Jumpinpin in south Queensland shows that dusky flathead have a protracted spawning period with serial spawning during summer (November to April). They are rudimentary hermaphrodites with sex determined at an early juvenile stage. Sex ratios are skewed with males most common in the smaller size-classes (< 50 cm TL). Mid-sized females (45 cm - 69 cm TL) dominate the production of eggs due to their abundance in the spawning aggregation. Within the female component of the spawning aggregation, the occurrence of individuals exceeding the current maximum size limit of 75 cm TL is low (2.6%). Parasitic nematodes (philometrids) occurred in 8% of ovaries. Degenerated ovaries, in which atretic oocytes are common, are present in half of the very large females (70 cm - 75cm TL) examined. The current minimum size restriction of 40 cm TL for dusky flathead provides protection for 73% of males and 15% of females within the spawning aggregation. 

Hi Sunny Boy, 

The project as a whole is not focussing on the specific location of individual FADs, but as FADs are clearly a fisheries enhancement tool that aims to increase angler satisfaction, there is little or no case for putting them in areas that people can't fish. 

Correct!!! 

Bond University academic Dr Daryl McPhee will lead a national project on regulation and policy associated with the planning and deployment of offshore artificial reefs and fish aggregating devices around Australia.

Dr McPhee said the project is a collaborative project which includes the University of Tasmania, national industry bodies for the commercial and recreational fishing sectors, the engineering company Stantec (formerly Cardno), the Australian Fisheries Management Authority and the Queensland Department of Agriculture, Forestry and Fisheries.

The project is supported by funding from the Fisheries Research and Development Corporation and the Department of Agriculture, Water and the Environment on behalf of the Australian Government.

Dr McPhee said that well designed and sited artificial reefs and fish aggregating devices (FADs) are clearly acknowledged as being able to benefit the marine environment and marine fisheries. They are widely deployed in developed and developing countries.

“Artificial reefs and fish aggregating devices can contribute to the UN Sustainable Development Goals as they can address economic, social and environmental issues in concert,” Dr McPhee said.

“In many countries regulatory frameworks are lacking or ineffective in the planning and management of artificial reefs, but fortunately in Australia we do have a mature regulatory framework that can adapt to change.

“As manufacturing technologies advance, new information on the biology and ecology of marine resources become available, and community aspirations change; there is need to better understand what regulatory and policy settings can best deliver optimal outcomes in our changing world.”

Dr McPhee said it was critical that planning and implementation of artificial reefs considered all ocean users.

“The ocean is inherently multiple-use and we need to ensure that the deployment of artificial reefs and FADs provide the optimal benefits without unforeseen impacts on other stakeholders and the environment. This is achievable.”

Dr McPhee said he is extremely grateful for the leadership and support of the Commonwealth Fisheries Association and the Australia Recreational Fishing Foundation in identifying the critical need for the project.

Hi all, 

I have been working over at Amity Point on Stradbroke and was able to get a little bit of a fish in here and there. More importantly, Drop Bear popped in and gave my students a fantastic talk on the oyster reef restoration projects that show much potential for restoring ecological structure and function within Moreton Bay. The students found it very enlightening. 

The fishing was patchy with a larger collection of smaller fish to bother me than usual, but the variety of retained fish was good including Moses Perch (both species), grassy sweetlip, squire, wire netting cod, grassy parrot, silver trevally, and stripey. The surprise catch was a cobia that was safely released after a quick photo. The squid improved during the time I was there, but there were much less than I expected. 

Here's a short video of some of the fish we got and a bit of the action off the mothership. 

Swains Reef Trip October 2018 - YouTube

Hi @Kat, 

I just buy the bloodworms from Jacobs Well Bait and Tackle, but you can still catch plenty of big whiting on yabbies. I use the same approaches that have worked for me for a long time. 6lb mono, No.4 hook and as small a sinker as possible. 

There are big whiting from the mouth of the Nerang right up to Paradise Pt at the moment. 

Daryl 

The kid and I have been doing well on the landbased whiting in the Broadwater. Today was a really good day in terms of the quality of the fish, with the best being 44cm. 

Cribb Island worms were the bait. 

Some solid bream this weekend at Shorncliffe Pier on yabbies with the best going 41cm. 

It was another good day at Shorncliffe Pier. Cribb Island worms and yabbies produced a nice mixed bag of fish for a few hours effort in the afternoon. 

That information is for black bream (Acanthopagrus butcheri) which does not occur in Queensland. Our species is the yellowfin bream (Acanthopagrus australis). 

Here is dome information that I have previously published: 

"The yellowfin bream belongs to the Family Sparidae. There are about 155 species in the Family with a further four species encountered in Queensland being the snapper, fryingpan snapper, tarwhine and the pikey bream of more northern waters.

Most coastal areas of the world have at least one species of sparid fish present. Globally, important recreational species in the family include the white steenbra of southern Africa, the common dentex of the Mediterranean and surrounding waters, and the sheepshead which is found in the western Atlantic from Nova Scotia to Brazil and is most abundant in Florida.

The yellowfin bream is endemic to the Australian east coast – meaning that is the only coastal region in the world where the species occurs. They are found in a variety of coastal habitats including throughout river systems, along all the coastal foreshores of Moreton Bay, the surf zone and around rocky headlands.

Let’s look at the likely movements of adult yellowfin bream in a given year.

While they can be found anywhere, from October to April they tend to be in the rivers and creeks (or at least adjacent to them) feeding in these diverse and highly productive habitats. The condition of the fish in October tends to be poor and they use to be referred to as “razorbacks” when I was teenager at Sandgate. If there is substantial rain over the summer period they do end up highly dispersed, but they still tend to be more abundant in around the rivers and creeks. The spawning period for yellowfin bream in Moreton Bay is centred around the winter months (with a peak in July to August), with spawning occurring at, or adjacent to, surf bars. As the day length shortens the fish from May onwards are stimulated to commence their migration to their main spawning locations, although they may have already moved downriver for example in the Brisbane River and the Pine River in March/April. They do not leave the rivers and creeks en-masse and not all fish participate in the migration so there are some fish available in the rivers and creeks all year round. It is likely that some fish go back and forth to the principal spawning locations during the winter from adjacent areas. Whether the proportion of adult fish participating in the annual spawning migration varies between years is unknown.

Yellowfin bream do not readily utilise the more open expanses of Moreton Bay and tend to hug the shoreline and this is where they can be targeted. When fishing the shorelines you are fishing along their migratory path. Unlike sea mullet, yellowfin bream feed along the way and their energetic needs are likely to be higher, hence they are hungry and will readily take a bait.  Why do they migrate to the surf bars? By spawning on the flood tide, they maximise the dispersal of larvae throughout the system. It is a good breeding strategy. Most post larvae enter the estuary at night during the full moon on the flood tide, and the transition from planktonic animal to a juvenile fish which occurs from August to November when the fish are 13-14 mm total length. From September onwards, most of the spawning bream are heading back to the river and creeks. 

Much of the early work on the reproductive biology of yellowfin bream in Moreton Bay was undertaken by Dr Barry Pollock who grew up on Redcliffe Peninsula. The reproductive biology of yellowfin bream is complex, involving a form of sequential hermaphroditism called protandrous (male first) sex inversion. This is not uncommon among fish species, and it is an approach which can maximise the reproductive output of a population.

Yellowfin bream possess an ovotestes in which the testis and ovary occur in separate zones within the same individual. Most juveniles become functional males, but a small proportion of juveniles develop directly into functional females (primary females). Protandrous sex inversion commences after the fish mature when male fish change into female fish; however, some fish remain as males (primary males) throughout their life. The upshot of all this is that most small adult fish are males and most large adult fish are females.

Yellowfin bream are thought to become mature as males between 17.5–20.5 cm fork length. The minimum legal size of 25 cm total length allows over 50% of fish to spawn once which is a standard benchmark when setting a minimum legal size.

The age of most species of fish, including yellowfin bream, can be estimated by examining otoliths (ear bones). Yellowfin bream are relatively slow growing, but not as slow growing as their cousin the black bream which is found in southern NSW and Victoria. There is substantial variation in how old a yellowfin bream is for a given size. For example, age estimates by the Queensland Department of Primary Industries identify that a 30 cm yellowfin bream would likely be seven years of age, but it could quite likely be as young as four or as old as twelve. Six year old yellowfin bream comprise the most common age group harvested by recreational fishers. Overall, fish in the four to ten year old age groups account for the majority of the harvest (86%).

It is fair to say that yellowfin bream are highly opportunistic in what they eat and this is well known to anglers who can use a myriad of baits or lures to catch them. Their natural diet though is highly dependent on their habitat at the time. For example, the diet of fish in mangrove and saltmarshes is dominated by shore crabs while terrestrial animals such as insects, spiders and lizards are also consumed."