Whats This Fish??

[murf]

thanks kc interested to know more as you find it and how you go with government departments. Some good quality pics to the Australian museum etc would not go astray and they never say no to receiving them. They like a pic on a plain background and with some sort of size ref ie rule

cheers Murf

[kc]

I'm going to run it up the flag poll at the Bowen round of fisheries management consultation and back it up with images and available scientific data. Don't think it will do much good but at least I will have them scratching their heads. Also my mate Dave Donald is launching into it with an article in NQ Fish & Boat. It is already on their facebook page and getting a lot of comments. There is no doubt what these things are and how prolific they have become. The issue is wether they are indemic or introduced and comments from senior fisheries is that "there is no evidence to show they are introduced"....typically there is no evidence to show they are not. What has come to pass is they are also showing up at Hay Point (coal terminal off Mackay) where they have not been seen before. They have spread in the Whitsundays to an area of close to 200 square kilometres (from less than 10) in what appears to be the last 5 years. If they ever reach the reef....look out. See the sounder images above. Solid Indos...wall to wall with any other species that used to live there being squeezed out or out competed. I am really concerned about these things and the only effective way of even slowing them down appears to be sustained recreational effort. Years ago guys would go out and catch an esky full, 50 or 60 and it appeared to restrict their range. After the green zoning and the bag limit changes the population has literally exploded, as has the range. They are now less than 20 miles from the reef. Once they hit that they have an open highway as far north and south as the temperatures allow. I predict, if the spread we have witnessed here is repeated, these fish may dominate the reef fishery within the next 20 years. The commercial line fishery guys should be made aware of this issue as well.

[grahams]

I reckon we have caught them around Port Clinton, Central Queensland. Generally one or two every second trip. Haven't seen any small ones. All about 45cm. They are basically large mouth Nannygai with proper teeth, and a heavier build. I narrowed them down to Indo's or one or two of the rarer lutjanids but Indo makes a lot of sense now reading the thread.
Nearly all of them have come from a couple of particular locations, near coastal, 20 to 30m deep, same habitat as grassies. Have not caught them on any of our recognised Nannygai country and not witnessed any large schools of juveniles (yet). Caught 2 on the inshore fern country this Easter.
Probably first noticed them around 2007. But my memory isn't good so they may have been there way back in the 80's. They are clearly different to nannies, halfway across to fingermark maybe? Got their mums colour scheme and their dad's build?

[Daintreeboy]

Sounds like they are a very slow moving fish in terms of colonising new areas. That would definitely help in eradicating them if it was at all possible.

[kc]

You have described them pretty well Grahame. Large mouth "nanny" with real teeth and built like a fingermark. makes them an nice little fish but I have not seen one 45. About 42 is the biggest I have seen. The big issue with these things is the literature says they can double their population in 15 months, which is staggeringly fast for a lutjandid which are typically very slow growing, so if a few hundred become 1000 and at the same time rec pressure is knocking a few off no big deal. But what about when 1 million become 2 million and there is bugger all rec or commercial pressure and this is what is going on here. It is dead easy to pull 100 fish in a 2 hour session and leave them still biting their heads off as ferociously as they started. There are literally millions of them in some spots and everything else, the grassy's, trout, large and small mouth nanny's seem to be gone or at the very least outcompeted for a feed. IMO Indonesian snapper are a clear and present danger to the biodiversity of the GBR lagoon and within a few years, about the only bottom fish that will be caught in the Whitsundays and, eventually, beyond. From a fishing for a feed point of view, it won't really matter a rats bum. They are plentiful, easy to catch and a great feed, but the boffins and save the reef crowd should be going off their nuts about these things as a threat to biodiversity.

[Matt_F]

Hi All, to get a correct ID I suggest getting a specimen to the museum in Townsville. Maybe the local fisheries mob can assist in getting it there. If it is an uncommon or introduced species they will use morphometrics to get an accurate ID.

[mmmouse]

It's rare for anyone fishing the islands these days not to have some number of indos in their bag. They are real, and are in big numbers here and are not hard to identify, unfortunately the pics shown in this thread aren't great. Interestingly, my wife's family (local since the land at airlie beach was under a grazing lease) have a photo from the early 80's that when I saw it I was sure there was an indo in the catch. Will endeavour to find and post the photo and even send it to the museum.

[kc]

Looks like JCU are going to do some work on these in Feb next year. They will look at the geneolgy to see if they come from a narrow gene pool (meaning all stemmed from a few individuals which would make them introduced) or came from a wide gene pool (meaning they are native). This will at least be a starting point to know one way or the other. Something is wrong or "out of balance" down here at present and it is a real threat to biodiversity.

[kc]

Below is official press release from JCU in respect of a study to be undertaken. At this at stage planned for the 10th to 13th Feb for sample collection. Nice to see that keeping this issue up in lights has finally produced some results.

Indonesian Snapper in WhitsundayWaters.

Some questions are about to beanswered

For some years debate has raged as to whether a locallycaught fish “Lutjanus biteanatus” or Indonesian Snapper are a native orintroduced species to the Whitsundays and this question may well be resolved asa result of a study to be undertaken by JCU researchers starting in February2015. This fish, with a recent history of rapid expansion and perceivedsubsequent displacement of more recognised local species has been protected bya bag limit rule designed to protect all “Tropical Snappers”. The bag limit removedrecreational pressure on this species over the last 5 years. Anecdotally, theIndonesian Snapper population in the Whitsundays has grown from a small pocket offish in Long island sound to totally dominate many of the areas, usually thedomain of more familiar species such as grassy sweetlip, large and small mouth nannygaiand red emperor. Perceptions that “Indo Snapper” are displacing “more familiar” species, canbe addressed by comparing abundances of familiar species and Indo Snapper inthe region over time. We also need to know what each species eats, how they interact, howthey tolerate different conditions. Answering these questions needs detailed studiesand experimental work to test how each species performs in given conditions. JCUresearchers have shown that species respond differently to various conditions. Onepossibility is that Indo Snapper are “invading” south along the Barrier Reef, butother possible scenarios include greater production by Indo snapper than morefamiliar species; changes in fishing pressure on Indo snapper and more familiarspecies, that may be affecting abundances.
Local recreational fisher Kevin Collins has worked for someyears with fisheries, managers, political parties and industry representativesto help uncover the history of this fish, not officially identified in the areauntil 1996 and says the outcome of this preliminary study will hopefully resultin a clear answer as to where these fish have come from. Whether the effect ofthe imposed bag limits has ultimately contributed to the recent population explosionof this species, is also a concern to many local anglers. “We hope to justknow” said Mr Collins. “Something is out of balance”. “Either these fish belonghere or they don’t and if they don’t, we would like to be part of the solutionand part of the control mechanisms to keep them in check”. “This is a prolificspecies in areas around the islands now and as far out as the Edward Islandgroup, areas we have never seen them before”. “Many fishers believe that a baglimit on “Indos” is like having a bag limit on carp or tilapia, but at least theIndonesian Snappers taste better,” he said.The pilot project does need to secure funding and recreational fishersare encouraged to be part of the solution by donating funds at local tacklestores. “If we want answers, if we want to see if bag limits should be kept oran open fishery declared so that recreational fishers can help control thespread of this species, we need to raise some funds and advise tackle shops ofany areas where the fish dominate, so that research staff can take samples”,said Mr Collins. “Doing research is ultimately a great outcome, because much ofwhat we know about this species is guess work and having JCU seriously involvedwill let science do the talking and help marry science with fisheriesmanagement policies, so that recreational fishing, fish stocks and local biodiversityare the winners”.
Ends