huge snapper -1
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Category: Saltwater Fishing
Forum Name: The Briny Bar
Forum Description: The place for general chat on saltwater fishing!
URL: https://www.fishing.net.nz/forum/forum_posts.asp?TID=3430
Printed Date: 21 Jun 2026 at 9:16am
Topic: huge snapper -1
Posted By: Eric de Vries
Subject: huge snapper -1
Date Posted: 24 Jan 2004 at 10:54pm
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Some info emailed to me on the above mentioned topic on snapper. In this case some light shed on the 'Bump on the Head' seen on some of the large snapper we see photographed often in magazines or here on this forum. * Bumps do increase with size and/or age. It's not clear which of these factors is more important. * Bumps do not inevitably form with increasing size or age. * Bumps occur on both male and female fish. * Bump-headed (often called "old-man") snapper seem to be more common in some localities than others. The Nelson Bays (Sounds to Golden Bay) snapper, which seem not to mix freely with Cook Strait and West Coast North Island snapper, were one such place, at least in the past when big fish were commoner. West Auckland/Northland, and parts of the Hauraki Gulf, were others. * Such fish are not common, and presumably will become less common as commercial and recreational fishing pressure reduces the number of old fish (snapper can live to 60+ yrs). * Bump-headed snapper are possibly relatively more common, or at least are written about and pictured more frequently, in Australia. * The bumps result from the enlargement of particular skull bones. Some enlargement can also occur in the lower vertebral spines just behind the vent - not visible until the fish is filleted. Similar bone enlargement occurs in other marine fish species, as the following abstracts of papers will show. You may have noticed that some large New Zealand trevally (Family Carangidae) also have "enlarged foreheads". The condition is called hyperostosis, which really just means excessive bone growth. Its cause is unknown. One explanation I've seen is that it's simply a way for the fish to store excess calcium. In any species of fish, it always occurs in the same bones - often at the front of the skull, and in lower vertebral spines. Thus the snapper is a typical example. * I have not heard the theory that it is used to open shellfish and kina, but think it very unlikely. The powerful jaws of the large snapper with such head bumps would be much more capable of doing this. Some references: Meunier, FJ; Bearez, P; Francillon-Viellot, H (1999). Some morphological and histological aspects of hyperostosis in the eastern Pacific marine fish Prionotus stephanophrys Lockington, 1880 (Triglidae). Proceedings of the 5th Indo-Pacific Fish conference, Noumea - New Caledonia, 3-8 November 1997. pp. 125-133. Abstract All the fish studied show the same hyperostotic bones: both frontals, the ethmoid complex, both operculars and one or two caudal vertebrae. Hyperostosis was always found in the 21st vertebra and sometimes in the 20th and 22nd. The cranial bones show a typical and regular thickening. On the contrary, in the case of the vertebrae, this thickenning concerns each side of the centrum only. The swelling of all these bones is the result of an active osteogenesis associated with resorbing processes resulting in the deposition of spongy acellular bone. This cancellous bone is surrounded by a thin cortical primary bone. Thus, the histological characteristics of the swollen bones of Prionotus stephanophrys are the same as those already described in the majority of other hyperostotic species, regardless of the bones involved. The causality and the biological signification of the hyperostotic phenomenon in P. stephanophrys seem unclear in the current state of knowledge but, given the particularly specific vertebral swelling of this species, this fish could represent an interesting model to study the etiology of hyperostosis. Smith-Vaniz, WF; Kaufman, LS; Glowacki, J (1995). Species-specific patterns of hyperostosis in marine teleost fishes. Marine biology 121(4): 573-580. Abstract The occurrence of swollen or hyperostotic bones in skeletal preparations, preserved museum material or whole fresh specimens of marine teleost fishes was identified in 92 species belonging to 22 families. Patterns of hyperostotic skeletal growth were typically consistent and often species-specific in all individuals larger than a certain size. The taxonomic distribution of hyperostosis in diverse phylogenetic groups suggests that it has arisen independently many times. Selected bones from two species of the family Carangidae, horse-eye jack Caranx latus and crevalle jack Caranx hippos, were examined in detail by light and electron microscopy. Nonhyperostotic bone was acellular (anosteocytic), while the hyperostotic bone contained osteoid-producing osteoblasts, resorbing osteoclasts, occasional osteocytes, and a rich vascular network, all characteristics of cellular bone. Thus, these fishes have a spatial juxtaposition of cellular and acellular bone tissues in adjacent and often serially homologous bone sites. The functional significance of hyperostosis is unknown, but it is a predictable manifestation of bone growth and development for the many taxa in which it occurs. Gauldie, RW; Czochanska, Z (1990). Hyperostosic bones from the New Zealand snapper Chrysophrys auratus (Sparidae).Fishery Bulletin 88(1): 201-206. Abstract General hyperostoses are well known in fossil fish bone literature (Tiffany et al. 1980). Hyperostosic bones have been described as occurring as nodules on the ventral pterygiophores as well as other bones of Recent fishes. Consistent occurrence of hyperostosic bones in many species has been taken to indicate that they are not pathological. Various roles have been suggested for hyperostosic bones ranging from aids in fin erection to hydrostatic correction. Meunier, FJ; Desse, G (1986). Hyperostosis in the Teleostei: Description, histology and etiological considerations. Ichtyophysiologica acta (Lyon) no. 10: 130-141. Abstract Hyperostosis are hypertrophied bones that can affect different levels of the skeleton in Teleostei. Generally, the hypertrophy is the result of an abundant osteogenesis with remodeling giving spongy bony tissue. Hyperostosis have been described only in fishes with acellular bone and living in sea water. The etiology of this phenomenon in fishes is unknown. Mechanical factors during swimming and with aging seems to be the predominant cause for hyperostosis. I trust this information will be of some interest. Courtesy of: L J Paul, Fisheries Scientist, National Institute of Water and Atmospheric Research, Wellington. cheers eric |
Replies:
Posted By: Redfinger
Date Posted: 25 Jan 2004 at 5:20am
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Nice of you to burn the midnight oil to provide that Eric. What the hell am I doing up at this hour? Off to Hen and chicks - yipee!! |
Posted By: Eric de Vries
Date Posted: 25 Jan 2004 at 6:57am
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Leave those big kingies alone will ya. Might have to plan a trip up there with Mr Matthews. good luck eric |
Posted By: Wefaknis
Date Posted: 25 Jan 2004 at 10:21am
| Eric, every time I see your avitar It still cracks me up. |
Posted By: Kerren
Date Posted: 25 Jan 2004 at 10:58am
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funny as duck!!!...certainly amussing! Thanks for the heads up Eric.....do you think (Dr??) L J Paul would be interested in helping us out from time to time with sticky ichthyological questions from the forum? perhaps we in turn could help him out with specimens and first hand experiences etc etc? Let me know...happy to approach him! ------------- I am Kermit, Leader of Muppets Nov 05 |
Posted By: Eric de Vries
Date Posted: 25 Jan 2004 at 4:02pm
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Kerren. I actually wrote to Malcolm Francis but he was just about to leave for a months holiday in Australia. He therefore passed on the questions to Larry Paul. Nice bloke. I would say that they (NIWA) are open to any feedback/questions we have, if need be. I have requested science papers before and they are happy to mail them out to you. Give it a try. Malcolm Francis has written several books about fish/reeffishes in New Zealand. You will find his email address in the NIWA site. Larry Paul contact mail is: mailto:[email protected]">[email protected] cheers eric |
Posted By: Toad
Date Posted: 25 Jan 2004 at 6:15pm
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This is from a book called Fish Might Fly by Australian marine biologist Julian Pepperell. It's a good book, goes into a lot of the fishy things that we fishos puzzle over.
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Posted By: Toad
Date Posted: 25 Jan 2004 at 6:16pm
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continued ..
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Posted By: Toad
Date Posted: 25 Jan 2004 at 6:17pm
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continued...
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Posted By: Eric de Vries
Date Posted: 25 Jan 2004 at 6:48pm
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Nice one Toad. Even to see some 'extreme bumps'. We get to find out more and more about these great fish. The skull bone growth is pretty amazing looking. All that calcium makes them pretty tough fish. And to be eaten by any other fish must be a job and a half. cheers eric |
Posted By: Peter da Squid
Date Posted: 25 Jan 2004 at 10:17pm
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If I gave a snapper head like those ugly bastards to my oldman to eat He'd have a heart attack! ------------- Good for Nuthin |
they are seriously deformed.