Effects of Tail Grabbing?

[Gr8KarmaSF]

Previously there was a video link showing how some wild rays were being handled and caught in Brazil. During the video it showed the rays being held up by just thier tails. I cant find the thread! Can anybody find it?

Just for the sake of discussion, do you guys think such handling could have any short/long term effects? If so what? Any damage to the body? Possible negative reaction towards humans? etc.

 

[coeus]

not really being an expert (yet) i dont see it causing any serious damage because they arent bony fish... im sure they dont enjoy it and it adds ridiculous amounts of stress to the ray for no reason

 

[Conner]

It will separate the vertebrae (or cartilage, whatever) at the base of the tails, essentially breaking them. I handled sw skates this way when I was on a commercial fishing boat in Alaska last year, and if you lifted them too fast, or swung them around (not me, other crew members), you could actually hear the vertebrae popping and separating. This could obviously result in damage to the spinal column.

Depending on the severity and placement of the injuries, it could just mean that they wouldn't be able to move their tail, or it could possibly damage internal organs/systems, such as the reproductive,respiratory, or digestive systems, leading to death.

 

[Gr8KarmaSF]

It will separate the vertebrae (or cartilage, whatever) at the base of the tails, essentially breaking them. I handled sw skates this way when I was on a commercial fishing boat in Alaska last year, and if you lifted them too fast, or swung them around (not me, other crew members), you could actually hear the vertebrae popping and separating. This could obviously result in damage to the spinal column.

Depending on the severity and placement of the injuries, it could just mean that they wouldn't be able to move their tail, or it could possibly damage internal organs/systems, such as the reproductive,respiratory, or digestive systems, leading to death.

Wow, interesting....

Anybody think that this practice might add to the mortality rate of wild rays being shipped out of their native country?

 

[Steve_89]

Wow, interesting....

Anybody think that this practice might add to the mortality rate of wild rays being shipped out of their native country?

It could...

I have seen documentaries where locals have been very rough with the handling of the rays...particularly if they have been caught up in the nets.

How about handling rays like this?

 

[lincolngoh]

It will separate the vertebrae (or cartilage, whatever) at the base of the tails, essentially breaking them. I handled sw skates this way when I was on a commercial fishing boat in Alaska last year, and if you lifted them too fast, or swung them around (not me, other crew members), you could actually hear the vertebrae popping and separating. This could obviously result in damage to the spinal column.

Depending on the severity and placement of the injuries, it could just mean that they wouldn't be able to move their tail, or it could possibly damage internal organs/systems, such as the reproductive,respiratory, or digestive systems, leading to death.

Ditto, that why i still don't buy WC, rays with such spinal damage, they may look ok, they may eat a little but linger on slowly for months before breaking your heart.

 

[Tom]

It could...

I have seen documentaries where locals have been very rough with the handling of the rays...particularly if they have been caught up in the nets.

How about handling rays like this?

WTFX!!!!

 

[sam buckle]

This could be an interesting subject. i Dont know if most of you know but on freshwater rays their is an organ next to the rectal gland which is responsible for the immune system. i am only summising but if this would damaged the ray would die a slow death as it became immuno deficient. so maybe damage to the base of the tail would cause this.
Here is a section from a published paper
"
The white lobes associated with the rectal gland undoubtedly represent the
"lymphoid tissue" described and figured in several earlier accounts of the gross
structure of the rectal gland (e.g., Hoskins, 1917). Their histology indicates
that they are a part of the Iymphomyeloid system of cartilaginous fishes recently
discussed by Fange (1977). This system is active in haemopoiesis and in the
immune responses. Components of the system mentioned by Fiinge include the
spleen and thymus; the epigonal organs (associated with the gonads); Leydig's
organ in the esophagus; extensive tissue in the cranium (in holocephalans) ; and
aggregations of leucocytes in the connective tissue of the kidneys and the intestine
(spiral valve)."
in larger elasmobranchs it is known that poor handling also causes damage to internal organs(especially the liver) due to the fact they are cartilaginous therefore having no stiff ribs forming a protective cage as in boney fishes.

so any rough/heavy handling of rays will result in a slow death which would not be visible for a short period of time. possibly weeks.

i shall ask my friend who has a docterate in marine biology and used to work with sharks at the Deep public aquarium in hull, his opinion on this.

Hope this was interesting
oh here is the link to the paper i took the info from http://www.biolbull.org/cgi/reprint/154/3/508.pdf