SHIPMENT OF CRAB EGGS
Date: 11 January 2000
From: Mohammed Al Rumaidh <Malrumaidh@bcsr.gov.bh>
To: Crab-L@ios.bc.ca
QUESTION:
I am a Phd candidate at the University of Wales, working on investigating the population dynamics of the swimming crab Portunus pelagicus around Bahrain waters. I intend to ship some egg masses to the UK in order to examine the larval development. Can you advise me please, what is the appropriate method by which I can send berried females or egg masses from Bahrain and get them arrive in the UK in a good condition, taking into account that the travelling time is 7 hours?
Mohammed Al-Rumaidh,
Fishery Researcher,
Environmental & Biological Research Prog.,
Bahrain Centre for Studies & Research,
P.O. Box 496,
Manama,
Bahrain.
Fax: (+973) 754822
E-mail: Malrumaidh@bcsr.gov.bh
***************
COMMENTS:
The American blue crab, Callinectes sapidus, is shipped live as a
postmolt (stage A). Crabs are refrigerated at between 8-10 C,
covered in moist seaweed or newspapers in cardboard boxes. The animals may
survive for up to 5-7 days when held this way. Watermen hold them in cold
rooms waiting for shipment. Temperatures below 8 can be fatal to the
crabs. We've transported blue crabs at room temperature (and on
newspapers layered over ice) in coolers for 10-12 hours but they need to
keep their gills moist. I've seen blue crabs in markets in San Francisco,
so they were able to make a 6 hour flight.
I've shipped ovigerous Cancer crabs a few times. We place a few
animals in a cooler, cover with seaweed (or moist but not dripping
newspaper), put a few blue packs (ice packs) on the top, and ship
air-freight express (or in our case drive them 7 hours north).
I've read that Scylla serrata can be shipped at room temperature,
covered in moist sawdust. They can survive for up to 7 days this way.
If possible you may want to ship the crabs with their claws glued
shut.
Cover the crab with a towel to avoid losing your fingers. Place
a small band of latex tubing over the claw and place a drop of superglue
between the claw and the band. This works very well as a restraint. The
superglue dries quickly even when moistened by water. Makes the crabs
easier to handle, and reduces their ability to fight each other while
getting bumped around on an airplane.
I don't think P. pelagicus is as hardy as C. sapidus. P. pelagicus is
tropical so it may not survive a lower temp. We've transported them
for at least two hours in coolers layered with blue ice packs. But don't
overdue the ice packs. The idea is to cool them down, not chill them. You
may want to try crabs with clutches in a range of stages. One stage may
ship better than another.
Expect to lose a shipment or two or at least several animals.
Ovigerous
animals may not tolerate the handling or temperature stress. Also,
we've noticed that egg mortality in blue crabs increases dramatically with
heat stress. So you'll want to watch for aberrant development and fungal
infections in embryos. A pretreatment of pen-strep at 500 mg/l ea. helps
against bacteria, and amphotericin-B is useful against fungi.
You must have someone ready to baby the animals along (i.e. watch
them load onto the plain) in Bahrain and someone ready to receive (i.e.
watch them unload) immediately upon arrival in England for this to work
well.
Work out the logistics for their transport ahead of time. You don't
want
to be waiting at the airport wishing you'd brought more ice packs or
seawater or money for additional shipping charges.
You may have to check with customs officials re the transport. You
may be able to transport them as "food" as opposed to "research
animals".
Don't cover the animals with water or they will suffocate. They need
to be moist, not dripping wet. While I haven't tried it, it makes sense to
not feed the animals before shipping.
Be sure to incinerate the shipping containers, and hold the crabs in
quarantine so as not to introduce unwanted organisms. Flow-through is
nice, but you don't want to introduce a fungus, bacterium, or invertebrate
larvae where they don't belong. Same goes for their egg masses. They have
a disparate fauna all their own.
Fish are often transported with extra oxygen. I haven't tried this
with
crabs. Blue crabs tolerate gas-bubble disease reasonably well, so you
may not have to worry about oxygen poisoning.
Jeffrey Shields
Assistant Professor
Virginia Institute of Marine Science
Gloucester Point, VA 23062, USA
Tel (804) 684-7128
Fax (804) 684-7186
E-mail : jeff@vims.edu
URL: http://www.vims.edu/~jeff/
http://www.lam.mus.ca.us/~tcs/