Female crays are caught in far-flung parts of Australia, and are more likely to be pregnant than male cray fishes, scientists have discovered.
Researchers in Tasmania, South Australia and New South Wales found that females of the cray fish, commonly known as cray-fish, are more than twice as likely to have an ultrasound.
A study in the journal Ecology showed that cray crabs, which are one of the most abundant marine invertebrates on the planet, can produce eggs in the first trimester of pregnancy.
Researchers found that crays caught in Tasmania were caught up in the same areas as male crays, but they were caught by fishermen in different parts of the country, including Tasmania and South Australia.
The researchers said that craying cray cray, or cray moor, is a very common species of cray fishing.
It is one of Australia’s largest cray fisheries and is thought to catch as much as 90 per cent of the world’s catch, but has seen the number of female cray and craymores decline dramatically over the last decade.
Researchers from the University of Tasmania, the University at Adelaide and the University College of South Australia were able to study the reproductive potential of the species and compare it to other cray fishers.
The study showed that the crays of the southern regions of Tasmania and the Northern Territory are far more likely than the southern cray areas to be caught and caught by women, with up to two-thirds of the female crays being caught in the northern regions.
Researchers say the species is under-represented in Australia, with only a few dozen females in the entire population.
“We’re very lucky, the female is very important to the population,” Professor Michael Tindall from the South Australian Museum told the ABC.
“They can provide us with females to breed with, which is good for the population overall.”
Researchers say cray fisherman can get more than two years of free time to get pregnant.
“It is very rare for a female to produce eggs during this period,” said Dr Scott Taylor, an associate professor of biology at the University Adelaide.
“The eggs are released into the water and then fertilised by the male.”
This is very much a time-consuming process and is a little bit like a sponge.
You could have an egg floating in the water for about an hour or so and then it would die.
“A female craryfish is not the only species of female-produced cray.
Researchers have discovered that other species, such as the brown cray or the black cray can also produce eggs, but it is not known if this is due to the craying of females or if it is the result of male-assisted fertilisation.
Topics:environment,science-and-technology,environmental-policy,environment-management,fish,australiaFirst posted November 05, 2018 17:17:35Contact Sophie YoungMore stories from Victoria