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(Sound of greater scaups)
Hi, I’m Derrick Jensen and this is Resistance Radio on the Progressive Radio Network. My guest today is Katharyn Boyer. Her work is focused on the ecology and restoration of coastal habitats, primarily salt marshes and seagrass beds. She is particularly interested in how species interact to structure their environments and influence fundamental ecosystem processes such as nutrient cycling. Such basic ecological research has important implications for the restoration of damaged habitats. Today we talk about seagrasses.
So first, thank you for your work, and secondly, thank you for being on the program.
KB: You’re welcome.
DJ: So what/who are seagrasses?
KB: Seagrasses are a group of flowering plants that live in the oceans, as the name suggests. There are about fifty different species that grow around the world, and they’re different from each other in terms of how they look and exactly how they act, but for the most part they have long blades and they go with the flow, in the water. They’re very flexible blades that provide habitat for all different kinds of organisms that otherwise wouldn’t have a place to live in the oceans, and also provide all kinds of other services and functions that we value, such as clearing the water, taking up nutrients, sequestering carbon, all those kinds of things that we value as humans.
DJ: I’ve heard them spoken of as “underwater meadows.” Is that reasonably accurate?
KB: That is accurate. Some are more continuous beds of blades coming out of the sediment, so they look more like meadows in that way. Others are more patchy. In San Francisco Bay, for example, our beds are very patchy. The plants are quite large and they tend to not grow in really close proximity to each other. There could be a meter between each patch that might be a meter in size. So depending on where you are, it can be more like a meadow or more like a series of patches of blades.
DJ: So just to be clear, when people think of bladed beings growing in the ocean, they might think of kelp, and we are definitely not talking about beds of kelp. These are completely different species, a completely different class of creature, correct? Different class of being.
KB: That’s right. Kelp is a kind of algae, and algae don’t have roots. They have holdfasts, so they grab onto rocks. They don’t have a vascular system like you think of in humans, with veins; and plants, flowering plants have a system of veins that move materials up and down through the tissues, called the xylem and the phloem. And that’s what seagrasses have, so they are actually true flowering plants, whereas kelp is a kind of algae, it’s a whole different group of organisms.
So seagrasses all have roots, and these roots are used to take up moisture and nutrients from sediments, which is not something that kelp does.
DJ: What do we call the ocean bed where they live? If it were land it would be called “soil” so what substrate, what do they grow in, what is that called?
KB: Well, you could call it soil, but we call it sediment. So it’s soil material, it’s soil particles like clay and silt and sand that have accumulated on the bottoms of bays and estuaries. And we call those sediments, so it’s a sedimentary process, this accumulation of these soil particles at low positions on the landscape or seascape. And those build up and provide the place for the roots to grow into for the seagrasses.
DJ: And how deep in the water do most seagrasses live?
KB: That really varies. It depends on how much light there is. So if the water’s really clear, seagrasses can grow in many meters of water. They can grow ten meters down. But in places where there isn’t a lot of light that penetrates, say there are a lot of sediment particles in the water, or there is a lot of small single-celled algae we call phytoplankton, in the water; that blocks the light, and if that’s the case, these plants are rooted in the sediment, and they’re sitting there hoping for some light, to put it in very human terms. They need that light for photosynthesis, so if there’s a lot of material floating around in the water column that blocks that light, then the seagrasses can’t grow as deeply.
So, for example, in San Francisco Bay, where we have a lot of sediment, in particular, floating around in the water column, there is very poor light penetration. And that means the deepest that our seagrasses grow is a couple of meters at most.
DJ: So what was, prior to seagrass habitat being destroyed – are seagrasses all over the world – were they widespread? And are they widespread?
KB: They are widespread. They occur in temperate and tropical places. They occur in very cold places as well. So they are very widespread, pretty much any place where there is shallow water and where there is also some protection. So you tend to not find them on the open coast that’s really beaten up by waves and wind, that kind of high-energy condition that you can picture along an open coast. So think about places where there’s some protection; bays and estuaries and lagoons where there is seawater that comes in, but it’s not coming crashing in. So seagrasses need flow, they need water flow, they don’t like to be in really still conditions because they need lots of exchange of water. They need clear, fresh, not fresh as in lacking salinity, but fresh as in clean water. And that means that you find them in protected areas where there is good water exchange, but not with such high wave energy that it would rip them out of their habitat.
DJ: Because they’re in bays often, does this mean that they’re often not in the saltiest of water, but they also like brackish water, many of them?
KB: They can take some lower salinities. So if you consider seawater is about 34-35 parts per thousand salinity, many seagrasses can live in that high of a salinity, but they can also live in salinities down to, say, 15 parts per thousand. So in estuaries and bays where there’s a mixing of fresh water and salt water from the tides, they can live up into the estuary to some extent. So if you move further up the estuary, where you might find 15-20 parts per thousand salinity, you’ll start to find other submerged vegetation that we tend to not call seagrasses for obvious reasons, they’re not in seawater anymore, they’re in something much fresher. But those are the counterparts of the seagrasses that continue to march right on up through the estuaries into completely fresh water. But these are other species than what we call seagrass. We call them just submerged aquatic vegetation, or SAV.
DJ: So before we get to the larger seagrass communities and also to threats to seagrasses, there are a couple more technical things I’ve been really wondering about. One of them is, how does pollination work? Because they’re pollinated plants. I understand insects, I understand wind, but I don’t understand how pollination would work underwater.
KB: Well, it is surprising to a lot of people to know that plants can pollinate underwater. Seagrasses do produce pollen and that floats in the water and that is how the pollen moves around and you actually get pollination. So it’s surprising, I think, to a lot of people, that that can happen. And it is just by water motion that that pollen gets moved around and the plants get fertilized.
But there is some evidence, some pretty cool work that’s been done on a seagrass species in Mexico, where it appears just through time lapse photography, it’s been shown that some small invertebrate species, little isopods, amphipods, those sorts of little shrimp-like animals, may be moving the pollen around, similarly to what bees would do in air, with terrestrial plants.
So we don’t know, still, what the extent is of that contribution, of animals, to the pollination of seagrasses. It might be small. But it’s not nothing, we do see evidence of it. But it is probably mostly just from movement of the pollen in the water.
DJ: So when I was doing the research for this interview, I came across something, and let me know if this is incorrect. These plants are kind of the plant equivalent of marine mammals in that they didn’t evolve in the ocean as such, but they came on land and then they went back to the ocean. Is that accurate or am I all wrong on that?
KB: No, that is correct. They did start as land plants, some probably in fresh water and some probably in saltier water, y’know you can have salty water on land, depending on what the geology of the location is. And so yes, it’s happened multiple times through evolutionary history, where these different species, they’re not even all that closely related to each other. You know I told you there are 50 species? I think there are 12 different genera, you know different genuses, of seagrasses, which means there’s a pretty diverse group that managed to perform the same act of migrating back into the ocean after being a land plant.
DJ: So seagrasses are home to other beings as well, are they not? Don’t they make larger, aren’t they parts of larger communities that include the little shrimp-like beings, fish, etc.?
KB: Yes. And that’s one of the reasons we do restoration of these seagrass habitats, one of the reasons why we’re really interested in conserving them. There are all sorts of little critters that live on the seagrasses. And those can be snails of various sorts, some with shells and some without. There can be those little shrimp-like animals like we mentioned, isopods and amphipods, just a wide variety of small critters, and then move on up from there through the food web, the things that eat those, gravitate towards the seagrass beds in order to find those sources of food, so we call those mesopredators, mesograzers. And then we get the larger predators, say larger crabs and fish that’ll come in and eat those midrange sized species that eat the small amphipods and isopods. And then, you know, keep on moving up through the larger sizes in the food web. You’ll get birds, such as herons and egrets that will eat the fish and the larger crabs. So the seagrasses really are the basis of a very complex food web that serves a whole variety of different species.
DJ: And I seem to remember, I don’t remember whether this was on your website or if I read this somewhere else, about how there is sometimes a relationship between seagrass beds and mangrove areas where the babies might grow in one and then move to another for rearing, is that accurate?
KB: That is absolutely accurate. There’s been some interesting work that’s found, particularly with coral reef fishes, large coral reef fishes, that if the coral reefs are adjacent to seagrass beds, and especially also if those seagrass beds are adjacent to mangroves, in these tropical areas, that in those places in the mangrove roots and seagrasses where the younger, the juvenile stages of the fish can live and hide, and find things to eat and grow up a little bit before they move off into the coral reef where it’s a more dangerous place; that they’re more successful by the time they grow up and move onto the coral reef. So there’s this value of having these adjacent habitats, and these complex habitats where the small versions of these animals can live and grow before they move out into more treacherous areas where they’re going to find predators.
DJ: There’s another topic I want to touch before we move to some of the threats to seagrass. I don’t remember what the figures are, but I’ve read some extraordinary figures on the capacity of seagrass beds to sequester carbon.
KB: We know some about that. There’s a lot of work going on, on that topic, right now, in seagrasses around the world. And there are some tropical seagrasses in particular, in the Mediterranean region, that have a tremendous capacity for storing carbon. They have these big, almost like peat reserves that you would find in some kinds of wetlands. But these are under the water, in the shallow waters. And those plants, those particular species have a tremendous capacity for storing carbon. There are others that we know less about, and that we suspect, because they’re a little more ephemeral in their nature, they kind of come and go, and they spread, and some of the shoots die while others are growing, and they probably don’t store as much. So it’s definitely a hot and ongoing research topic to try to understand which species and where there is that capacity for the seagrasses to really perform that function in a big way.
We know they all are sequestering carbon, because they’re photosynthesizing and they’re taking carbon out of the water, and, you know, they’re building their tissues with that carbon. And so they all are sequestering carbon, for sure, but whether or not they’re doing it in a large way compared to, say, terrestrial trees, that’s something that’s still being investigated.
DJ: You said two words that reminded me of another question. One word was “Mediterranean” and another was “ephemeral.” And I seem to recall reading, awhile ago, about a seagrass bed in the Mediterranean that some people think is one of the oldest beings on the planet, like older than bristlecone pine? Does that sound familiar?
KB: It does, yeah. There have been some genetic studies done that have shown that there are some seagrasses beds, and I don’t know whether this is the one you’re referring to or not, but that they are like a single being, they are a single clone, and they have lived for a very long time, and they have spread, but a blade or a shoot, from one end of the bed to the other, and they could be kilometers across, is identical genetically to a blade at the other end of that same bed, suggesting that these are very old and they’ve been in place for a very long time, spreading and providing that habitat.
DJ: You said that seagrass beds often are in bays and estuaries, and oftentimes bays and estuaries are where people put cities, and oftentimes cities are then associated with pollution, and disturbances to the bay itself. So if we had a time lapse map of healthy seagrass beds over the last 500 to 1000 years, would we be seeing a shrinkage and movement in the wrong direction, and if so, what are some of the primary threats?
KB: Well, you’re absolutely right that these estuaries and bays and lagoons that occur along our coasts around the world are often the places where people want to live. And there are many threats that come along with that. It’s just that human cohabitation with these same environments where the seagrasses live. In many places there has been a decline in the acreage of the seagrass, the overall health of those beds, and that can come from habitat destruction, it can be from, for example, dredging through a seagrass bed in order to provide access for boats to marinas and that sort of thing. It can be, you know, when we build bridges and tunnels, when we put structures over water that would shade the plants, things like docks and marinas. We do have those kind of direct impacts on the acreage there might be of a seagrass in a particular location. And then on top of that, we landscape, we have our agricultural use of fertilizers and those bring nutrients, particularly nitrogen, into these waters, that seagrasses didn’t evolve with, and that can often lead to algal blooms. The algae can grow on the leaves of the plants themselves. It can grow loose in the water and shade those seagrass plants. So there are many places where nutrients themselves have been a huge detriment to seagrasses and how much acreage there is and how healthy they are. So lots of different impacts, including other things like invasive species. In some of these coastal areas where we do a lot of shipping, we bring invasive species, invertebrates like I was referring to earlier, the amphipods and isopods; there is a number of examples of invasions of those from locations far from the location we’re talking about. And those come in and now don’t have predators that are used to them. Their populations can explode, and we can have damage to the seagrasses due to them.
That’s something we’ve experienced in the San Francisco Bay with a non-native, an invasive amphipod that has come in from other places. And instead of eating just the algae on the leaves, which is typical of the amphipod in its native habitat, it eats the plants themselves, and can really devastate, particularly the fruits and the seeds, remove huge amounts of those from the plants, but also eats the leaves, and so can be quite damaging. This is something that is a problem for us in the San Francisco Bay when we’re trying to do restoration, because sometimes when we go to collect those flowering shoots that we use to produce new seagrass beds using the seeds, these seeds have all been eaten. And also we’ll see these outbreaks of this amphipod in the places that we restore. We bring the plants in and we remove the amphipods as best we can before we do any of the restoration, but these amphipods still find their way to the restoration site and then eat the plants.
So those kinds of things, those movements of animals around, can be very detrimental. And there’s also examples of invasive seagrasses coming from different places, that humans have facilitated the movement of, and then those species that don’t belong there compete with the native species of seagrasses.
So that’s a variety of examples. I’m sure I could think of more if I spent long enough pondering it. But many things that humans do in these coastal areas have negative impacts.
DJ: I’m wondering too about dams. I know that dams deprive the lower rivers, and also the ocean, of a lot of sediment. And so, for example, when they took out the dam on the Elwha, on the Olympic Peninsula, there were some rocky beaches that were only rocky beaches for the last 100 years, ever since they put in the dam. As soon as the dam was taken out, it refilled with sediment and that brought back all sorts of species who were supposed to live on the sandy beach there. So I’m wondering, too, since these plants live in sediment, whether dams are also depriving them of sediment.
KB: That’s a really interesting issue now, the whole management of sediment, the availability of sediment as we think about sea level rise. Because we know the oceans are rising, and that includes in these estuaries and bays, like I’m talking about, where these seagrasses live, and as the water levels rise, these plants may or may not have the opportunity to migrate upslope where they can still get that light, depending on whether or not there is actually migration space, a gentle slope that is not developed at the top.
So we’re interested in this issue of “Is there enough sediment?” for example, to allow the plants where they currently are to rise in elevation, right where they are living, so that they can still persist after the sea level rises.
In San Francisco Bay we’ve had a huge input of sediment through the Gold Rush period, when there was the hydraulic mining of the Sierra foothills, so that’s the blasting of the hill slopes to remove gold during the Gold Rush years. So from 1850-ish to about the year 2000 we had a tremendous amount of sediment coming down through the San Francisco estuary, and allowing some of these shallow areas to build up in elevation and keep place with sea level rise. That’s already been occurring.
But now we’re seeing this clearing of the water and we’re very concerned about whether or not the seagrass beds, the wetlands that are a little higher in elevation will be able to keep up with sea level rise, because they’re not going to continue to have this influx of sediment.
So it’s an interesting thing, right? Because it was a human-caused source of sediment, and we got used to that over a 100 year period, or a 150 year period. And that became the new normal for this particular estuary. Now, when that stops, and you were talking about dams, a lot of the remaining sediment that was coming off these hill slopes is back behind dams all around the Bay area. And so that means that those sediments are not coming down and not supplying that elevational capital, if you will, to allow the seagrass beds and the wetlands to rise in elevation as the sea level rises.
And there are examples of that sort of thing, where humans have gotten involved in the management of sediment, either through damming or hydraulic mining, or other kinds of activities, and so depending on where you are, it could be a very different situation in terms of whether there will be enough sediment to keep up with sea level rise as it proceeds.
DJ: You said earlier that the seagrasses seem to have very specific requirements as to how deep they can be, based on how much light comes through the water column, and that reminds me of something. For whatever reason, I wrote maybe 100 pages on the various mass extinctions in a book five or six years ago. And until I did that research, I was just like everybody else, I pretty much thought okay, so maybe a meteorite hits or something and then it changes, it makes it get really cold and then the dinosaurs die. That’s pretty much as much as I thought of it.
But I remember reading that with every single mass extinction, a significant part of it has been with a change in sea level. And as soon as I read that, it made perfect sense, because those areas are some of the most fecund on the planet. And then when you put that together with the seagrass being able to live, let’s say one species can live between two and four meters underwater, if the sea level rises two meters, and runs into rocks and can’t have soil there, that whole community is going to die.
KB: That’s right. It means, in a lot of places where we’re thinking about what’s going to happen as the sea level continues to rise, there may be places where we don’t have any opportunity for those kinds of habitats, over time. So, say in 50 years, or 20 years, those places may run out of space.
And then there are other places where there is migration space. And so it means that managers and people who are thinking about “How do we maintain these habitats within the estuary, broadly?” Who are thinking about “Where can we focus our attention? Where can we get the most bang for our buck?” in terms of our conservation dollars, to enhance or restore or encourage these habitats to be able to do that migration. That could be buying up adjacent lands, or preventing development in certain areas, or conservation easements and that kind of thing, really focusing those efforts on places where we think there is the room for these habitats to migrate, as opposed to our shorelines where we’ve built right up to the edge and we have seawalls and riprap and we have no opportunity unless we’re willing to take out our human infrastructure to allow for those habitats to move.
DJ: So before we talk about your beautiful phrase “repair, enhance and encourage” seabeds, can you talk about your relationship to seagrass, and how did you … why seagrass, and not butterflies? What is it that draws you to seagrass?
KB: Well, I was like many kids who thought that the oceans were an amazing place when they were growing up, and thought they would be a marine biologist and study whales and dolphins, or maybe sharks. Along the way I realized that whales and dolphins and sharks and sea otters and all those things that are so appealing to humans; first of all there isn’t room for everyone to study them. There are only so many positions in which to do that. On top of that, those highly charismatic species are fed by all the little things in the ocean, and the little things in the ocean are what started to fascinate me. So the plants that harbor the amphipods that are eaten by the crabs that are then eaten by the birds, you know. As you go up through the food web, it’s those little things that run the whole system. And it became fascinating to me that this was the case. And it wasn’t obvious to me, growing up and taking my early science courses, and thinking about what it meant to be a marine biologist, that that was really a path for a marine biologist, to study the plants, for example, in the water.
So I became interested in that much more recently than when I first became interested in marine biology. It really took until I was out of my undergraduate program and into my graduate work, where I realized that I wanted my focus to be on those habitat-forming plants, including the salt marsh plants, but eventually the seagrasses that were so fascinating to me. Without them you don’t have habitat. You cannot support all of those higher organisms. So they’re just absolutely critical and that became my focus then. How can we conserve them? How can we restore them? How can we create these places where everything else can thrive? And that’s been my motivation now for my whole career since my Ph.D.
DJ: You know, when we put it as bluntly as you just did, it’s all so obvious. How can you expect other creatures to survive when they don’t have a home? It’s like how can we expect – of course on land, meadowlarks are going to start going down in population if you kill all the meadows. Or monarch butterflies are going to if you kill all their food. It’s the same with the seagrass. They’re sort of the foundation upon which everybody else rests.
KB: That’s right. We call them foundational species. I don’t know whether you knew that, but that is a term that we use for seagrasses and kelp forests and a number of different habitat-forming species. They don’t have to be plants. Corals are an example of a habitat-forming species. Or mussel beds. So those could be animals that form the habitat, but they really do, we call it a biogenic structure. Through their bodies, they provide the habitat for a whole host of other organisms.
DJ: In your bio, there’s a line about how species interact to structure their environments. And are you meaning that in the terms you’ve been talking about so far, basically just providing habitat? Or are you also meaning that in terms of – I know, for prairies, prairie grasses build tremendous amounts of soil. How are you meaning that, when you say that you’re interested in how species interact to structure their environments?
KB: I’m thinking about those biological interactions between species. It could be plant to plant or animal to plant or animal to animal. But through that biological interaction, how do they influence the physical aspects of that environment? So, like you say, how do they trap soil? How do they accomplish nutrient retention and removal from the environment? How important is it that each of those species is present in order for that physical process to actually occur?
And so I’m really interested in that aspect of the biology of these systems. Not just the biological interaction but how that interaction ends up influencing the physical aspects, what the architecture is of that habitat. So, how big are those plants and how much do they sequester carbon and how much do they trap sediment and nutrients and that sort of thing.
So it’s really that juxtaposition of that biological interaction and that physical response, that I get really fascinated by.
DJ: About ten years ago I got really obsessed with the question of who’s in charge? I mean that loosely. And thinking about how parasites affect the behavior of their hosts. Like the ones that certain snails will get, and it makes them crawl to the top of a rock and wave themselves around to attract a bird, because that’s the next one who’s going to eat the parasite. And there’s one in specific, that had to do with bays, that blew me away. It was a type of parasite who is, I believe, eaten by a snail, who is then eaten by a fish, and who causes the fish to then go up and flash its belly. And what that does is then make it easier for seabirds to eat, which is the next step. And so seabirds eat it, seabirds then poop the parasite back out, the snail eats the poop and it starts over.
And the reason I bring all this up, is the thing that blew me away is that at some point, somehow, somebody had done a study where they found that if you remove the parasite, the whole system falls apart, because without the fish swimming to the top to flash their bellies, it’s too hard for the seabirds to catch fish. So basically the parasite ends up driving everything.
Those sorts of secondary and tertiary effects that we don’t think about immediately, just blow me away. I’m thinking about this just in terms of how species interact to structure their environments. I’m just marveling at nature, that’s all.
KB: You can turn that around, too, and think it’s important that you have all those connections, all those different exchanges of the parasite through all the different levels of the food web. Something people like me do is look in a restored site, or a site that is damaged, and we look to see if you find the parasite present in all those different levels. We know that they’re important enough that if they’re lacking, that there are functions that are lacking, and that tells us that we have not successfully restored. So there’s a parasite that infects snails in salt marshes, for example, and if you don’t find that parasite throughout that food web; there are a number of different steps where that parasite normally travels in order to complete its life cycle. Then you know that you have not successfully restored that tidal marsh habitat.
DJ: Tell us a little bit about your efforts to restore, enhance, and encourage – I love that phrase – seagrass beds. What do you do, or what do other people who are working on these issues do?
KB: In San Francisco Bay, that’s where my work is focused, we are attempting to restore a particular seagrass called eelgrass, and it occurs at about 3000 acres of the bay right now, but we think there’s the potential for it to occur at about 30,000 acres. An order of magnitude more area. And that’s based on biophysical modeling that has looked at the depth available, the light penetration, the flow, a number of different conditions that we know are important for seagrass growth. And predicted where we ought to be able to have this particular species of seagrass, the eelgrass.
And we use that, then, to, as a starting point, anyway; to say “This particular location in the San Francisco Bay ought to be able to support eelgrass, and it’s not.” So we start there, and we bring in eelgrass that we’ve collected from other locations, natural eelgrass beds, and we either seed it or we transplant it, and I can tell you about the ways that we do that, if that’s of interest. We establish it in this new location in very small plots. And we watch them, and we let the seagrass tell us whether or not that’s a suitable location.
So we could measure all different aspects of the soil conditions and light, and we’ve done that very grossly through this biophysical modeling work. So we have some sense of that. But we don’t bother to do the really detailed measurements at a specific location. We plant the seagrass and we let it tell us whether it’s going to be able to grow in that location.
And if it does not, we move on. Sometimes there are places where the model suggests we can get eelgrass established, and the plants don’t grow there. And there are other places that we’ve been quite successful with.
So we plant the plants and we are working to try to expand some of these restored areas, to have eelgrass in locations in the bay that we haven’t had in the length of time we’ve known where the seagrasses are. So it’s not like we have great historical information about where eelgrass was in the San Francisco Bay. So that’s a big lack. And in fact, we’re not that interested in where it was in the past, because we know that the bay is very different than it was in the past, from sediment deposition from the hydraulic mining, like we talked about, but also because we’ve changed the whole configuration of the bay. So we’re more interested now in saying “Where can it grow today?” Not so much “Where did it grow in the past?” Where can it grow today? And we are working diligently to try to establish it in these places where we think it can grow.
DJ: Let’s say that you start a new plot tomorrow. I don’t know if that’s what you call them. You plant some seagrass tomorrow, or the right time of year, this year. And it grows, and does well. What would be a realistic best case scenario for how quickly that could grow? So, you plant something – well, first off, how much do you plant? How big an area do you cover? And second, if things went just great, how big could it be in ten years?
KB: That’s an excellent question, and we don’t know the whole answer to that yet. We’ve been working on this for a number of years now, and the largest plots that we – plot is a good word – the largest plots that we have installed, or transplanted or seeded, are about an acre in size. And when you think of that acre, don’t imagine that it’s wall-to-wall eelgrass within that space. It’s not at all. We plant it very sparsely in that space, so it can spread and fill that space. We have to collect less from natural beds that we’re trying to conserve.
So, best case scenario, that acre would fill in with the eelgrass, within a few years’ time. We have not seen that happen yet. We’ve definitely seen expansion of eelgrass in places where we’ve planted, but we haven’t been doing this long enough to see it fill in the space in the way we would hope it to over time, if we can watch these plots for longer.
DJ: And if you have it in there for five years, have you started, or however many years, and it starts to fill in, have you seen the other associated species coming into that area?
KB: Yeah, it’s interesting. Most species that we expect to see will find that new eelgrass plot within a very short period of time. And that’s not surprising for species that have, invertebrate species that have, for example, planktonic larvae. So imagine a crab, for example, that has a larval stage that floats around in the water. When its larvae are dispersing around the bay, there’s this habitat, it just sort of happens upon it, voila! It stops and decides to live there.
But there are other species that we call direct developers, and those are species that – for example, some snails that produce baby snails that look just like the adult, and those snails don’t disperse around within the water column. They have to crawl to the new location, so species like that don’t show up as fast. Some of them show up faster than we would expect. But others, after five years, aren’t there. We now have been doing this long enough that we’re figuring out which of these species, even if they don’t have planktonic larvae, are still somehow managing to arrive at these sites without our intervention, and others that are not. So we’re thinking about now; should we be bringing those species in?
There’s this really beautiful sea hare, it’s green and has stripes on it, it’s like a snail without a shell. Long, gelatinous-looking animal. It gets to maybe an inch total in length. And it lives on the seagrass blades and eats the algae off the seagrass, allowing more light to come to the seagrass. And that particular species doesn’t show up at our restoration sites on its own. So, knowing that it’s beneficial to the seagrass, we’re starting to think that maybe we should be moving it in there and allowing it to do its job. Maybe we’ll have more successful restoration at these places if we do that assisted migration.
DJ: So we have several minutes left, and I think everything you’re saying is important and really interesting. For people who recognize the importance of seagrass to the world, and to those habitats, it seems like a harder habitat to directly – like, I have friends who love buffalo, and they can work on Buffalo Field Campaign to try to protect buffalo. And I know people who love other species, and they can protect habitat. It seems one thing to file a timber sale appeal, to protect a piece of old growth forest. But if somebody listens to this interview, they think “Wow, this is really cool,” they start reading up on seagrass, they fall in love with seagrass, what can they do? How can we help seagrass? It’s obvious how you can.
KB: Well, there are a number of things that people can do. They can participate in these restoration projects as they’re going on. It’s not for everyone. These are difficult places to work. They’re windy and there are strong currents. Not like the open coast, like I was referring to, but still. Some of these places we can only access by boat, and some places we have to crawl through mud in order to get to these seagrass beds.
So, there are opportunities for people to volunteer, but usually those are for more hardy souls, except for the work when we’re actually collecting the seagrass, and we rig it up on various – we have a couple of different ways that we take seagrass that we’ve collected. We attach it to bamboo stakes or popsicle sticks. There are various ways that we then do the transplantation, and we do that on land, so people can participate in that regardless of their ability to get around through mud and in water. So we just do that on land at the Romberg Tiburon Center.
So that’s one thing that people can do. They can also support, when there are opportunities to vote for measures that promote restoration, they can vote for those and they can decide that they’re willing to tax themselves in order to provide for this kind of restoration work. A lot of the funding that goes toward doing this kind of restoration comes from bond funds, in the state of California, anyway. Or from different measures where we have property taxes that then contribute to restoration work, including of seagrasses.
There are things that people can do with their pocketbooks and their ballots, where they don’t have to get anywhere near the water, if that’s not their thing and they just appreciate these habitats.
DJ: Are there people who are doing equivalent work to yours in Chesapeake Bay or the Gulf Coast, where people could … if somebody’s living in Alabama or Nova Scotia or Louisiana, and they want to actually do some hands-on work, are there places they could find to come and volunteer, like you’re saying in the Bay area?
KB: Absolutely. So you mentioned the Chesapeake Bay. There are programs there to restore the seagrasses. The coastal bays, along Maryland and Virginia have a hugely successful seagrass restoration program going on there, that has utilized a whole lot of volunteers. Along the Gulf Coast, where there was the Deepwater Horizon event, there’s a lot of restoration going on where there are opportunities for volunteers. That’s true throughout the world, so people just need to make a little bit of effort to see what’s going on in their area, and I bet they would find opportunities.
DJ: Is there anything you wanted to say about seagrass that I haven’t given you the opportunity for?
KB: Well one thing. I think there are a lot of people who don’t even realize this is something that’s in the water, because they don’t see it. And not just seagrasses, but a number of habitats that people are just not aware of. And I encourage people to go out, on the lowest tides that they can. There are these great apps you can get on your phone, for example, that tell you when the tides will be at their lowest point during daylight hours, and you can see where that might be in your local area. And go out at those lowest tides, because that’s when you will actually be able to see these habitats.
And I think if people see them, they’ll understand so much more about what they can provide and how valuable they are. When they’re underwater at the high tides, the general public is not aware of them, and so I think it’s hard to make the case to the general public, that they should do anything about these kinds of places. So if we can get them out on those low tides, and they can see them, they can explore them, I think we’ll find more support.
DJ: Well that’s just so great. And thank you so much for your work, and thank you for being on the program. I would like to thank listeners for listening, my guest today has been Katharyn
Filed in Interviews by Derrick Jensen