'Beagles are usually few and far between, but the boats fishing cod grounds south of the Cape are running into a lot of them right now. There is a pocket of life out there, and a good concentration of these sharks. There is no telling how long it will last. As far as targetting them on purpose - first and foremost, ask if it's cool with the boat when you make your reservation. Be considerate to other fares, which means bringing your heaviest 100+lb tuna gear, and setting the drag as high as you can stand it - a 150lb class shark shouldn't take more than a minute or two to get into gaff range if you use the right gear. A 400lb animal is a whole 'nother story. On the plus side, if you get one of those, you can compensate everybody on board for lost fishing time by sharing the steaks.
Like Dom said in another thread, there is a real ethical problem with killing these things - they are just too darn cute, and very scarce these days. I had a rediculously easy shot at free gaffing a 4' pup a couple of years ago, put my hand on the gaff, and couldn't bring myself to lift it out of the holder. To top off the cuteness factor, porbeagles and salmon sharks are the only two shark species on the planet that have been documented playing with inanimate objects - broken off lobster pots and such. These are curious fish with a playful personality. I'd much sooner put a gaff in a sea lion than a porbeagle.
Then again, they all have to die some time. If I were going to fish for them, I'd use a 3-5lb pollock, carefully vented and gently hooked in front of the dorsal, just through the skin. A haddock would be second choice, and a short cod a distant third. You want something that's shiny, wiggly, and bloody, the (il)legalities of using groundfish for bait not withstanding.
