| Copulation
record for Orectolobus ornatus (10.30am 1/8/98) On one of our survey dives to collect data for Marks integrated project we were lucky enough to find a couple of banded wobbegongs mating (and even luckier that I had my camera). Here are some fairly intimate pictures of the amorous pair. This record is particularly interesting as both individuals were under a metre in length (male 84 cm and female 86cm). According to Last and Stevens (1994) banded wobbegongs reach sexual maturity at 175cm (though a mature male was recorded in Queensland at 63 centimetres). It has been speculated that this may be a "practice" copulation of sexually immature individuals. From the records I have entered to date 114 of the 135 banded wobbegongs recorded have been in the 50 centimetres to 1 metre size category. This is by far the most common size range observed for this species in the area. Location and prevailing conditions: We found the wobbegongs in 3.5 - 4 metres of water on sand beside one of the boilers of the "Wollongbar" ship wreck. Fifty metres off shore from main beach at Byron Bay, northern New South Wales, Australia. There was a .5 to 1 metre swell (significant surge at the depth the observation was made) and visibility was 5 to 6 metres. The weather was overcast with a few showers and a lite to moderate west-north-westerly wind. Water temperature was between 16 and 18 degrees C. A number of wobbegongs were recorded (both species) on the transect at the "Wollongbar" and this may have been due to the presence of dense clouds of filamentous red algae (Ceramium sp?) blanketing the nearby wreck of the "Tassie II" (where no sharks were recorded on the day), displacing the sharks. The algae may have been an irritant to the predominantly bottom dwelling sharks. |
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| Observations:
Mark first noticed the sharks on the return swim of our first transect
on the "Wollongbar" and drew my attention to them. In this
shot you can clearly see the male bitting the female just behind the
gills (above the pectoral fins). This method of "keeping hold"
has been observed in other shark species including grey nurse (Charcharius
taurus) and previously in wobbegongs. Female sharks have been observed on other occasions with what appears to be mating scars. |
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 This
is a tail shot. Notice the unused clasper, visible protruding at an odd
angle. At the time of mating in other shark species one clasper is typically brought forward to help water enter the siphon and mix with sperm. The clasper is then introduced into the females vent. It was hard to tell if the male was using his tail for additional
leverage, the sharks were being washed around a lot by the surge. |
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| Here is a close up shot clearly showing the males clasper inserted in the females vent (maybe I should have put some sort of warning at the top of this page (oh well)). This was taken not long before the two sharks seperated. Despite the presence of divers (notably the one who lept repositioning them for the shots he wanted) and the surge, the sharks stayed together for 20 to 25 minutes (unsure how long they'd been together prior to discovery). |  |
| When the wobbegongs finally seperated (and finished attacking me, note for future reference that sex for sharks is quite an aggressive act and does not have the same calming effect as in humans) I tried to get a good shot of the males clasper. Notice the distorted shape. When inserted in the female during copulation the clasper flares out like an umbrella to anchor it in position. |
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| I'd be really keen to hear your feedback on this record. Are both sharks sexually mature or just the male? What conclusions can be drawn about the population from this record (if most sharks fit into this size range)? | |
