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  #1  
Old 06-14-2011, 02:02 PM
Squidly-Diddly Squidly-Diddly is offline
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anyone watch "Deadliest Catch" about Bering Sea crabbers?

and are there any good cut-away drawings of the ships and where and how big their crab-holds are, the water-refresh systems, etc? Do the boats always run with holds full of water and is there some permanent opening from the holds to the sea?

I saw a pic of a wrecked/beached modern crab boat of similar design, but comically short in relation to beam. It looked about the same beam as ships on the show, but must have been near 1 to 2 beam/length.

Size doesn't seem to be any secret, just technically weak American TV.



Show is mostly about them trying to find migrating swarms of crabs. Would it make any sense for a crabbing operation to send out advance chumming boats a week or so ahead and drop a few tons of bait into an area to coax the crab in and then target that area.

Sort of like deer hunters planting crops just for deer they plan on hunting, but different. The crabbers seem to be allowed to catch unlimited amounts of cod for bait.

Or would that be against the Crabber's Code?
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Old 06-14-2011, 04:16 PM
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marshmat marshmat is offline
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Quote:
comically short in relation to beam. It looked about the same beam as ships on the show, but must have been near 1 to 2 beam/length
It seems that's usually the result of poorly designed quota rules- this particular problem shows up everywhere.
Fishing quotas are supposed to be based on population biology studies- basically, "how many fish/crabs/whatever, of what sizes, can we take from a particular area without compromising the ability of that species to come back in similar numbers in the future".
But in practice, they often end up devolving into "maximum X fish per foot of boat length". When that happens, you get short, wide, fat, ill-mannered boats evolving to beat the quota rule, and the higher goal of keeping the fishery alive for future generations is lost or defeated.
I've caught a few episodes of the TV show, but never really went out of my way to watch it. That sort of fishing's not really my style.
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Old 06-15-2011, 09:38 AM
jehardiman jehardiman is offline
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Quote:
Originally Posted by Squidly-Diddly View Post
and are there any good cut-away drawings of the ships and where and how big their crab-holds are, the water-refresh systems, etc? Do the boats always run with holds full of water and is there some permanent opening from the holds to the sea?

I saw a pic of a wrecked/beached modern crab boat of similar design, but comically short in relation to beam. It looked about the same beam as ships on the show, but must have been near 1 to 2 beam/length.

Size doesn't seem to be any secret, just technically weak American TV.
In addition to the quota rules which force long deployments (all the days the season is open in some cases) that marshmat notes, there are financial and regulatory licensing rules which tend to reward shorter boats. In the crab fishery, the technical limiting factor is the stability with the trap deckload running out to the grounds and possible "burned out" lightship with deck trap load condition returning. This forces proportionally broader beam and more burnensome hulls.

Quote:
Originally Posted by Squidly-Diddly View Post
Show is mostly about them trying to find migrating swarms of crabs. Would it make any sense for a crabbing operation to send out advance chumming boats a week or so ahead and drop a few tons of bait into an area to coax the crab in and then target that area.

Sort of like deer hunters planting crops just for deer they plan on hunting, but different. The crabbers seem to be allowed to catch unlimited amounts of cod for bait.

Or would that be against the Crabber's Code?
That really won't work because the fishing areas are opened and closed based upon fisheries management decisions over a given time. This is what leads to the game of guessing where to fish and fast runs between open areas. See the site below:

http://www.alaskafisheries.noaa.gov/...ab/default.htm
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Old 06-15-2011, 11:12 AM
peterchech peterchech is offline
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Didn't Phil Bolger do alot of work towards the end of his life on designing efficient fishing boats that could be operated for far less money (ie diesel costs) and therefore bring in the same profit for a smaller catch?

Sounds like the existing regulations would not allow for this...
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Old 06-15-2011, 01:46 PM
Squidly-Diddly Squidly-Diddly is offline
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on the show the captains are always trying to guess where

where the swarm might be within a few miles and crab move about 1mph in their search for food.

They will drop pots and sometimes come up near empty but 20 miles away will come up full.

I'm pretty sure the broad areas to crab in are know months ahead of time.

So wouldn't dropping chum in an area starting a couple weeks ahead of dropping the pots tend to bring crab into the area?

Maybe start dropping chum evenly in a 20 mile diameter circle's area and start slowly decreasing the diameter to walk the crab in over two weeks. Then stop for 2 days and drop pots in a circle around the area.

The Bait Boat could be any boat able to hold a few tons of chum and wouldn't be REQUIRED to be out in bad weather or under any strict schedule, so this operation might only be feasible during decent weather.
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Old 06-16-2011, 07:29 AM
whitepointer23 whitepointer23 is offline
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Quote:
Originally Posted by Squidly-Diddly View Post
where the swarm might be within a few miles and crab move about 1mph in their search for food.

They will drop pots and sometimes come up near empty but 20 miles away will come up full.

I'm pretty sure the broad areas to crab in are know months ahead of time.

So wouldn't dropping chum in an area starting a couple weeks ahead of dropping the pots tend to bring crab into the area?

Maybe start dropping chum evenly in a 20 mile diameter circle's area and start slowly decreasing the diameter to walk the crab in over two weeks. Then stop for 2 days and drop pots in a circle around the area.

The Bait Boat could be any boat able to hold a few tons of chum and wouldn't be REQUIRED to be out in bad weather or under any strict schedule, so this operation might only be feasible during decent weather.
why don't you go on the deadliest catch website and tell them your idea. the skippers might be able to explain why they do it the way they do. have you considered where the currents might take your chum, i know some of the grounds they fish have strong tide and current influence.
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Old 06-16-2011, 08:47 AM
Village_Idiot Village_Idiot is offline
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Baiting an area is an old and well-known strategy that the fisheries managers are quite familiar with. Therefore, I have to assume that the regulations are designed such that this methodology would be illegal/impractical.

If baiting was being used and proved to be effective in this scenario, and could not be regulated for whatever reason, then other restrictions would be put in place (shortened season, reduced harvest numbers, etc.) to attempt to ensure that populations were not overfished (assuming everyone follows the rules).

Unfortunately, profit motives tend to sway all too many folks to rape the resources and ruin it for their grandchildren, and more unfortunately, they often don't realize the consequences of their actions. It's the old stick-your-head-in-the-sand mentality ("oh, if I take just a few more, it won't hurt anything"). This is true for all resources, not just crabbing.
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Old 06-16-2011, 12:10 PM
Squidly-Diddly Squidly-Diddly is offline
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Village_Idiot, I figured any improvement in catching would

be matched with quota regs, but it would still increase profit because they aren't wasting time looking for crab.

I was also wondering what being hauled up from 500+ft to sea level, then back down, does to all those crabs who aren't "keepers", but I guess most survive because they keep the "keepers" alive in tanks in the boats for days till port.

Any explaination of why crabs and other deep sea creatures don't get The Bends just from dissolved oxygen bubbling at the much lower sea level? Just not enough gas dissolved in their fluids in the first place?

I was thinking of a crab cage that would allow the smaller crabs to escape once the cage is disturbed(if the crabs even have the presence of mind to try) but I figure the bigger keepers would just block the exits in their attempts.
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Old 06-16-2011, 03:33 PM
Village_Idiot Village_Idiot is offline
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The biggest issue with surfacing from great depths is gas exchange. Aside from gas bubbles in our bloodstream, we humans have large internal air pockets that would allow our bodies to be crushed from pressure at greater depths. Most sea life do not have the air pockets, so don't have issues with pressure changes. OTOH, many fish have swim bladders, and many of those that do have trouble quickly regulating gas exchange with the bladder (which is why fish caught from deep waters often have swim (gas) bladders bulging from their throat. Tournament anglers have taken to using hypodermic needles to deflate the bladder of fish they are throwing back, but I think a remote-release cage would be easier on the fish (but harder on the releaser, which is likely why it isn't implemented). Anyway, crabs, being invertebrates, don't have swim bladders or bones, etc., so they don't have quite the issues. As far as gases in the blood, I am not familiar with the exact biological processes, but I think sea life has evolved to handle that issue as well. Some sea life has little use for blood - for example, there are fish that live in oxygen-saturated waters that have no hemoglobin in their blood because they don't need it for oxygen transport - their blood is transparent.

Btw, here's a link you might find interesting:
http://www.alaskankingcrab.com/fishing.html
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  #10  
Old 06-18-2011, 05:14 AM
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Lurvio Lurvio is offline
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I've been following the series for a few seasons. About the holding tanks, AFAIK they are filled when the boat is not being emptied. The water circulation is done with pumps that run water in the tank (probably in the bottom) and a screened outlet overboard (in one episode on one of the boats that screen had been broken/rusted out and the crew lost quite a lot of crab)

The boats in the show seem to be in the L/B range of 3-4. That stub version sounds like real bad idea for the area. In the show I've got the impression that the boats performance in rough waters is held in high value. Most of the captains have a long family tradition on the crabbing business.

Pre-baiting sound like there might be some health issues ahead and so I would presume it being forbitten.

Lurvio

Edit: Heres a wikipedia article about the series and the boats, the individual articles about the boats have some data about the boats. Wikipedia - Deadliest Catch #Vessels
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Old 06-18-2011, 06:24 AM
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TeddyDiver TeddyDiver is offline
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Bends aren't an issue for deep sea creatures. The partial pressure of nitrogen in deep water is the same as on the surface and in the atmosphere. Bends becomes an issue when you breeth air.
Human "air pockets" ventilate quite easily if you don't have any health or medical concerns. Fishes, depending of the species, have either closed or open swim bladder or some no bladder at all as all invertebrates (like VI said).
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