Depends on the weather and shots Most will say a D3 or a 1dsmk3 Though at 3 and 5 grand their a little pricey.
Though recently I completed a weeks shoot on a fishing trawler (Big waves) and the camera that I used was a nikon D70 with sb600 flash and the sigma 18-50 F2.8 lens Spray was the major problem so a UV filter is must due to the constant wiping with a towel. The D70 survived despite being hit three times by waves (important dry off immdately with towel) Though as back up I also had an Olyimpus 35mm on1 with it being total manual and devoid of eletronics.
The thinking behind the D70 was that there cheap enough and plenty enough that you can take the risks to get the shots Plus a 3 grand camera lost over board would be tempting to jump in after it.
There also is the option of underwater housing though these are pretty dear and cumbersum.
Remember one hand for the camera other for yourselfA camerasome lenseslights and eyesCreate your own stylehttp://www.flickr.com/photos/twaca/..
Take a look at Pentax K200d and Pentax K10d/K20d, as they are weather sealed. I also believe the in body SR could be usefull on a boat...
A package with the Pentax K10D and the DA* 16-50mm would be totally weather-sealed..
When having weather-sealed packages available at your budget, buying a D70 seems rather silly to me..
When you buy the K10D, you would have enough money for a flash and filters (Polariser is really handy when being on water). You could go for the k20D if you'd find a good deal somewhere although it would compromise your flash and filter quality a bit..
16mm is probably wide enough (and as wide as your budget allows) but I'm not shure if you like the 50mm. A friend of mine, nautical photographer, has got a whole bunch of lenses till 500mm but they do come at a price.The Weather sealed (* indicates that) DA* 50-135 would set you back another 700 dollar..
Apart from Pentax, I'm not familiar with other brands that make weather-sealed systems at a reasonable price.....
I use a sony a700 which has some weather sealing.
I store it all in a waterproof stormcasehttp://www.flickr.com/photos/scarab440/sets/72157605419290100/.
The majority of the pic Itake are also on the water. you should check out waterproof nylon covers to guard against splashes....
Thanks for the input. Is the polarizer also a u/v filter or do you need both? And if I were to get two lenses, what do you recommend?..
A polariser is different from a uv-filter. I use both, the uv-filter just to protect my lens from scratches (a uv-filter is about 25 $, much less than your lens). Whenever I've got enough light (polariser takes away 1.5 stop) and a bright sun, I take out the polariser which brings out the skies better (depending on the relative angle of the sun). It is a great tool to prevent the overexposed skies. This is quite a nice site with example images. http://www.cs.mtu.edu/~shene/DigiCam/User-Guide/filter/polarizer.html.
If weather-sealing is really important to you I would only get the DA* lenses. It might be worth it to look up other brands as well, I don't know anything about them doing weather sealing but I'm sure there must be some..