Seasonality to Seafood?
Is there seasonality to seafood? Is there a certain time of year that it tastes better with respect to fish and shellfish?
I don't know about tasting better, but there is definitely a seasonality to the availability of local seafood. For example, in the South, oysters are generally only available during the fall, winter and spring ( months with "r"), shrimp in the summer and soft shell crabs in the late spring, early summer.
The only eat oysters in months with an R, is an old saw that dates back to the years before jet transport and good refrigeration. Oysters were harvested in the northeast and shipped in barrels of ice via wagon or rail and could not withstand the May-August heat. Now that there is great refrigeration and fast transport, Oysters are available and delicious year round.
Here in Connecticut we have major Oyster festivals (Milford and Norwalk) mid summer.
The famous Copper River salmon runs are late May through September. As jla1960 points out, oysters are less desirable (but available) during the summer "no R" months, mostly because they are busy making little oysters, and their flesh gets soft and their liquor milky. Likewise, lobsters are "soft shell" in summer when they molt, and they are flaccid and filled with liquid. Bluefish in New England are voracious eaters, and are themselves good eating size around July-August. Stone crabs are restricted to a season from Oct. 15 to April 15. Other crabs have harvest restrictions. Most billfish have seasonal migrations and their peak catch periods are then, usually May in Mexico and Central America. Spiny lobster season in the Caribbean takes a 3 month pause beginning in March for mating. Grouper are subject to fishing bans when some bureaucrat has determined that enough have been caught that season and the "replenishment stock" must be maintained. The list is much longer, these are but a few examples of seasonality you inquired about.
It depends on what fish or shellfish you're talking about, and where you are. I'm an avid fisherman who lives in Northern California, so my notions of seasonality are informed by that.
Mushy farmed salmon is available year-round, but the wild stuff is a summer / fall phenomenon. Dungeness crab are a treat around the winter holidays. Halibut tend to be most plentiful when the weather starts to warm. Steelhead run in the winter, stripers in the spring, and the albacore, giant squid, and white sea bass show up only when they damn well please.
That's a scratch on the surface of the seasonality of seafood in my neck of the woods. Look on the internet to find posts by recreational and commercial fisherfolk where you are to find out what's best when. Or better yet, talk to them.
Seafood is especially seasonal. I guess most Americans wouldn't know that if they're just going to the supermarket seafood counter.
Here's a Japanese source for info on the seasonality of fish/seafood. The calendars are marked with the monthly percentage of annual yield, color-coded for easy viewing. You can put it through Google translate for some amusement.