Was fishing with a friend's daughter one summer on cape cod out of a kayak, we saw some bluefish finning slow, just the tips of their fins. She lobbed the cast right into them and man there was an explosion of energy, you'd think we threw a brick of lithium in the water. The blues went straight from sleep to kill mode. We were fishing surface poppers psycho blues were slashing at it en-masse, she was reeling that popper fast and the fish were like greyhounds chasing a rabbit. That in itself was super fun. She hooked one, others were slashing in from the side, trying to steal the popper.
At first we didn't see the seal, then we did, locked in, a torpedo wake. Gray seal, the big-uns, 500 lb sort of puppies. Well, you can't really tell a kid to reel faster because there's a seal coming, plus big bluefish on light spin gear are hard to horse anyway....I warned her in about ten seconds the rod is going to feel very different than it does with just the fish on it. That seal took her fish, the reel was running fast, the rod bowed big. I walked her through how to tighten the drag up and point the rod at the seal and held on as tight as she could. Before it broke off we had a Nantucket sleigh ride for about 10 yards. Allie (and I) still talk about it a decade later....
Now I won't cast if the seals are close. Kayaks and seals and other people's kids aren't exactly combos that always have great outcomes, Still, head on a swivel, you can't dismiss them.... Interesting the sealions at Spokane Street earlier this month had no problem getting their feeds without stealing fish, lord knows there were a bajillion chances to steal hooked fish from everyone there!
What surprises me about the harbor seals out here, the fish often don't seem that spooked...