Breeding time!

Ken Flanagan has confirmed the breeding time of Eastern Shovelnose Stingarees in PPB.
These two images show female Eastern Shovelnose Stingarees, Trygonoptera imitata at Brighton, Port Phillip Bay, Victoria. The photo on the left, which was taken on 6 April 2017 shows a fish that is not pregnant, the fish in the image on the right (photo taken on 3 February 2017) is clearly pregnant.
Clinton Duffy examined many observations of the species and made the following comments, "I haven't gone through all of the images but this gives you an idea of what's there; pregnant females apparent from December to early March; the mature males appear to turn up after the first pregnant females presumably to mate with them as soon as they are post-partum; I have included links to some of Ken's observations of what appear to be very small, possibly neonate, rays but that probably needs a closer look to confirm. Many of the pregnant rays appear to be associated with cover or rocky substrate but I'm not sure if that's a real association or not."
Last et al, 2009 state that, "Litters of up to 7 pups born annually in February or March ; pupping normally occurs in sheltered waters".
Thank you Ken, Sascha Schulz and Markus Stone for your observations and Clinton Duffy for your analysis.
Reference:
Last, P.R, G.K. Yearsley & W.T. White, Stingarees Family Urolophidae in Last et. al., 2017. Rays of the World. CSIRO Publishing. pp 790.
Posted by markmcg markmcg, June 02, 2017 04:25 AM

Comments

No comments yet.

Add a comment

Sign in or Sign up to add comments

Is this inappropriate, spam, or offensive? Add a flag