Time, tide, and temperature

It’s been hot here.

The average highs on Cape Cod through most of July and August are in the seventies. The high seventies, mostly, but even the high seventies are pretty moderate, by summer standards. This year, though, we’re seeing way too many nineties. Kevin, who doesn’t tolerate heat well, has tried to get it to break by letting his hair grow into a style that screams, “Seventies!”

It hasn’t worked, but it better cool down here soon – he’s threatening the mustache.

Our oysters aren’t liking this any more than Kevin is. Up to a certain point, they thrive on warming temperatures. In June, we had a nice stretch of the grow-grow eighties, and commensurate increases in water temperature. Our seed – 150,000 pinhead-size oysters – has thrived, and the largest are now almost an inch.

We left last year’s seed in the onion bags in which they overwintered until about a month ago, when we started opening the bags that seemed to be growing fastest. This week, we opened the last of those bags, and also sold the very first of that crop.

And that crop is very promising. They’re very uniform and well-shaped. They look like lightbulbs, with pointy ends that make them easy to shuck, and deep cups that indicate plump, meaty oysters within. There are almost no barnacles, and very little spat, so the shells are unsullied.

But the nineties are not being kind to them. If a warm spell coincides with midday tides, so the oysters are out of the water during the hottest part of the day, we always get some death. Every time we go out to the farm, we worry about what we’ll find. So far, it’s a been a few here, a few there – maybe two or three percent, total. But a percent here, a percent there, and pretty soon you’re talking about a sizeable loss.

This week is a bad one, with temperatures in the low nineties, cloudless skies, and low tides in the early afternoons. So, yesterday, we went out armed with a pump and a couple hundred feet of hose. We put the pump intake in the river (the channel, which doesn’t go dry at low tide) and ran the hose up to the farm. Every tray got a shower.

We have no idea whether this is going to help. The idea is that the oysters will cool as the water evaporates.  That’s the principle behind swamp coolers, and we’re hoping to make it work for us, but it may or may not be enough to save a few oyster lives. We thought about leaving one row unshowered, so we’d have a control group, but we figured we’d rather save the oysters than know we saved the oysters.

Both the short- and long-term forecasts are for the heat to continue. NOAA has us scheduled for above-normal temperatures for the foreseeable future – and NOAA foresees for over a year. So it looks like we’ll have to bear with it for a couple of months, and then we’ll have a race to the sixties. I hope temperatures get there before Kevin’s hair.

20 people are having a conversation about “Time, tide, and temperature

  1. i have a question.. because i don’t understand oysters enough and I’m sure you’re much better about considering these things. But I wonder about how oysters handle water. Like…. does it make them more susceptible rather than less? Like.. you know how to you water plants, but you’re told to water less often, deeper, rather than lightly water, more often. Because if you lightly water, the roots reach up to meet the water, and particularly in the heat of the day, it makes them susceptible. Could that apply here? Like, do they just hibernate of sorts during the heat and is this pulling them out of it and maybe having opposite effect?

    ps- yes. aware oysters are not plants:)

    • An excellent question! Oysters clam up when they’re out of the water, and a dousing isn’t enough to make them open up and think it’s time to feed again. So it’s just a matter of the water evaporating from the outside of their shells.

      Although your plant theory happens not to apply to my oysters, I think it’s one of the many reasons I lose so many plants!

  2. It sure has been unusually HOT. I bet some of those oysters and a beer would cool you off.. Question what is spat??

    • Oysters and beer are a cure for just about anything.

      Spat is baby oysters. Most of the farmers use triploid oysters, which are sterile, but there are some fertile oysters out there, and they spawn in the summer. Some years, there’s barely any set (that’s what we call it when the baby oysters settle on the hard surfaces out in the water), other years, a lot.

        • Theoretically, you can. And we were just talking to another oyster farmer last night who does just that. There are things you can put out to “catch” the spat, designed to be hospitable to baby oysters, and then scrape off the oysters and grow them like the stuff you get from the hatchery. But triploid oysters have a couple of advantages. They don’t spawn, and spawning oysters are not at their best for eating. They also grow faster, and that reduces our labor, and our risk. So we don’t collect spat.

  3. Good luck! Hope you don’t lose too many. And maybe even without the evaporative effect, that water from the channel is cool enough to bring the temps down a bit????

    • Al, there is a cooling effect, particularly when it’s dry and there’s a breeze. I’m sure we’d have more death if we didn’t have that. So far, we’ve probably lost between 2 and 8 percent, and we hope it doesn’t get too much worse.

  4. It’s the same up here. I’m actually glad that I have a lot of indoor work to do this summer, something I wasn’t happy about earlier. The lettuce is bolting, the broccoli is flowering and forget the spinach. I hope your oysters will be ok.

  5. Accidental Mick says:

    As you and Kevin haven’t already done this it is probably a stupid suggestion but remember I have only seen a few (too few 🙂 ) photos.

    Would it be possible to provide the oysters with a sunshade made from weed-suppressant sheeting? Perhaps it would be prohibitively expensive or perhaps the tides in the bay are strong enough to rip the sheets to pieces?

    • Mick, that wouldn’t be a bad idea at all. But it would have to be a stiff material, or the tide would definitely shred it. Later in the season, those trays will have grow-out bags on top of them, and that will shade them. If this heat were the norm, I suspect we’d be thinking about more permanent measures.

      As for the photos, I figure people have limited patience for picture after picture of something as low-energy as an oyster!

  6. Yes, it is way too hot. Thankfully, we are getting some rain with the heat this time so the bees are still foraging. Since you folks have a pump, I was wondering if you could rig up a system of hoses and the little impulse sprinklers (either up on rods driven into the mud, or maybe the kind pre-mounted to tripods) to provide the beds with cooling water for a longer period. Like an irrigation system. If a low tide coincides with the hottest part of the day, being able to provide a shower of cooler water might save quite a few shellfish lives. I also assume you could take other stuff to do with you when doing this so you would not “waste” time watching sprinklers or standing/walking/dousing. I’m also wanting more oyster farm pictures. hey are sort of a low energy subject, but pictures with words describing what I’m seeing let me learn a lot. Sending positive thoughts your way-cool water oysters taste better.

    • Greg — We could do that, but probably only theoretically. A system of sprinklers would be time-consuming to set up, and we couldn’t leave it out there (it would be destroyed, either by the force of water or by corrosion). We’d also need a much stronger pump, which would weigh a lot more. As it is, it’s quite a schlep to get a 70-pound piece of equipment in and out of a small boat. If it’s too heavy for one person to lift over the gunwale, it’s not practical. It looks to us that our best option, given the conditions, is to just walk a hose around. But we always entertain suggestions, so keep ’em coming!

      I”m glad your bees are still out and about. We hope to get back into bees next year.

  7. I agree with Accidental Mick – can you sew some shade-cloth on top of the wire baskets?
    Or even put it inside the baskets on top of the oyster-babies?

    Maybe some foam sheeting – like wetsuit material. Then when it was underwater, it would float to the top of the cage, giving the oyster-babies more space in the play-pen.

    • Kingsley, I think you and Mick should go into the oysters business. So much of it is solving problems just like this.

      Floating material can have a lot of uses on the farm, but it has to be cheap. Each tray is about 3×4 feet, and there are 250 trays. That’s a lot of material. The other two factors are labor and access. Putting a cover on a try, securely enough so that it won’t get ripped off by the water, is only possible if the material is stiff. And we have to secure it in such a way as to have access to the oysters, because we go through almost every tray every week.

      The heat cost us about 3 or 4%, total, I think — which we don’t like to see, but it’s not a huge financial hit. The cost/benefit for any solution has to be in our favor, and I don’t think there’s any tray covering that can be. But if it gets hotter, the equation changes. So enough with the greenhouse gases!

      • Oooh, I know … those foam rubber budget camping matresses.
        (The ones they also used at water-slides in the 80’s)

  8. Hot here in NYC. The little holes in the little boat, that’s one of the best little stories I’ve read in a while. Great Stuff! It is fitting a New England setting, the tinkering, the physics and math of it. Melville mentions them briefly in Moby-Dick, digresses, waxing philosophically. Nice story that.

    Happened to walk into the NYPL Book Store and this one caught my eye.
    Maybe you’ve read it, reviewed it, know the author…but maybe you’ve not heard of it, so here goes.

    Eat the City: A Tale of the Fishers, Foragers, Butchers, Farmers, Poultry Minders, Sugar Refiners, Cane Cutters, Beekeepers, Winemakers, and Brewers Who Built New York

    ROBIN SHULMAN is a writer and reporter whose work has appeared in the New York Times, the Washington Post, the Los Angeles Times, Slate, the Guardian, and many other publications. She lives in New York City.

    ISBN-10: 0307719065
    ISBN-13: 978-0307719065

    • Goose — Thanks for the recommendation (and the kind words). I did see something about that book, but needed the reminder to put it on my radar.

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