[00:00:00] Michael Hawk: Hey everyone, it's Michael Hawk. Can you believe it? We're already at the end of 2025. It's an incredibly busy time of the year for many of us, and unfortunately for me, I got hit hard with one of the many bugs circulating around. But I'm still able to bring you this episode today largely due to the help of our volunteer Amelia Heinz Botz.

Before we get into today's episode, I'm excited to share more about what we have upcoming in 2026. We have topics ranging from climate informed conservation to exciting discoveries on the road to recovering the Sunflower Sea Star. Incredible aphids, which you're gonna hear a preview of today, and the ecology of Salt Lakes among other amazing topics.

Today we have a special compilation episode looking at biodiversity, recovering everything from oceans to mistletoes, to even a mini preview of an upcoming episode that you'll hear in 2026 on aphids. Lemme tell you, I just love biodiversity. [00:01:00] I've always thought the term sounds a little bit bland, but the diversity of life is why we're here today.

Studying biodiversity reveals how food webs work, how agriculture prospers, how soil forms, and so much more. It also reveals the unique adaptations different organisms have developed, sometimes showing resilience and sometimes fragility. And very often it forces me to question how I look at the world.

And our first segment really illustrates that point because we're talking parasites. Now, when you hear the word parasite, you're probably thinking of mosquitoes or ticks or tapeworms. Nothing you'd want to invite into your home or property. But what if I told you there are parasites that are absolutely essential to healthy ecosystems?

In fact, there are many examples, but today we're focusing on one of the coolest plants I can think of mistletoes. Our guest in episode one 14 was Dr. David Watson. He's an Australian ecologist who specializes in mistletoes. mistletoes have evolved their parasitic lifestyle [00:02:00] five separate times across different plant families.

That alone tells you something remarkable is going on here. They provide food, shelter, and even dramatically cool the air in their immediate environment.

Dave's research shows that trees with mistletoes can be up to 10 degrees cooler than neighboring trees 'cause mistletoes are constantly releasing moisture. He's proposing that we intentionally add mistletoes to urban street trees as a climate adaptation strategy. Turning what Foresters once called Public Enemy number one, into a solution for our overheating cities, and that's not even talking about all of the biodiversity benefits that they bring.

This conversation really helped me realize just how critical some parasites can be. Let's listen.

how did mistletoes appear on the scene?

[00:02:53] Dr. Dave Watson:  All right, well, so firstly just a bit of a few facts and then we'll get into the history. So, mistletoes aren't [00:03:00] one thing. They're a way of being a plant. There, there's three things that they do that makes them a mistletoe. So they're parasitic, hemi parasitic, we talked about that already.

 They attach to their hosts above ground. So they're aerial and hemi parasitic. they're woody, so they've got woody tissues. Now you can think of all sorts of other plants that are two of those three, like dodder. dodder is an interesting one. It's an aerial hemi parasite, but it's not woody.

And then there's all those freaky little things that live in forest underst stories that attach to the roots, and they're not mistletoes. So aerial woody hemi parasites, those three attributes they have evolved independently on five different occasions. And they're not each other's closest relatives.

They always came from root, parasitic shrubs, woody shrubs. And three of those lineages are pretty minor, small groups of of plants in tropical forests, either in Asia or in Latin America. But there's two families [00:04:00] that have gone bananas in terms of diversification. And they account for the vast majority of mistletoes worldwide.

 So, those two families are what most people think about when they think about mistletoes. And when you look at them now, they're a very distinctive group of plants that have evolved independently and many of their their traits are convergent, but they popped up in the fossil record fully formed.

And so we don't really know much about, about the early history of that, but we get a few clues from looking at the way different mistletoes do their thing today. And recently I pieced together what little bits we know that they used to do and what they still can do in today's forests. And then looked at the history of when, of, when these lineages came to be.

mistletoes today depend on birds to move their sticky seeds around. If a mistletoe seed falls on the ground, nothing happens, it might sprout, but it needs to be on the branch of a tree, a living tree of a compatible species and then it can make a living. But if you look at the history of [00:05:00] it the switch from root, parasitic shrub in the forest understory to canopy, parasitic plant, a mistletoe up above, above the ground that predates birds.

 That happened ages ago. And the major transitions occurred around the 30, 30 million year ago Mark. there were birds around, but not the kind of birds we see today that move mistletoes around it. But it was right before songbirds became a thing. And so it looks like a. On two occasions at least, possibly four.

These root parasitic shrubs were moved into the canopy by mammals. In Africa, it's a group of mammals associated with the little dwarf lemurs and bush babies that you can find nocturnal critters in Africa and Madagascar, and then in Latin America a tiny little marsupial, the Monto del Monte the sole living representative of a whole order that used to be widespread in Gondwana all the way across Antarctica when Antarctica was forested.

And those two dudes were the first agents, as far as we can [00:06:00] tell, that took this root parasitic plant up into the canopy, either wiped off the seeds or defecated the seeds up there. And the seeds are like, Hey, look, we can actually do this. And that was right around the time when songbirds were emerging.

So I. Songbirds most definitely helped diversify mistletoes, but they weren't the agents that first explained that switch from the root parasitic to the aerial parasitic. That was our great grandparents.

[00:06:27] Michael Hawk: Wow. And, talking about a seed falling on the ground, maybe it sprouts, but it can't take hold. That takes me back to your earlier discussion about hemi parasitic and the fact that mistletoe can photosynthesize. So in, the lifecycle of a typical mistletoe, is the host plant just helping it through those initial stages to get it to a size and maturity where it can produce its own nutrients or is that mistletoe continually using certain specific [00:07:00] nutrients from the host plant throughout its life?

[00:07:01] Dr. Dave Watson: Good question. And it's the second part. So it's constantly taking water and whatever's in the water. But in most parts of the world, think of mistletoes as water parasites. What they really need is water. The rest they can make themselves and before they've attached to the plumbing system of the tree they've got a green seed.

Their seed doesn't have a seed coat, so it's a photosynthetically active seed. So it needs to be deposited in quite a well lit area because it needs to photosynthesize even as an un sprouted seed to power that initial growth and that initial push into through the bark to make that connection with the with a, with the vascular tissue of the host.

[00:07:37] Michael Hawk: So, can you tell me a little bit about what do they do beyond take from the host tree?

[00:07:43] Dr. Dave Watson: great. So they do a fair bit and they've been studied quite well. There's a group of mistletoes that are quite diverse in North America. Mexico sneaking up into Canada, but especially in the Western us they're called dwarf mistletoes. And they prioritize coniferous hosts, pine trees, [00:08:00] fir trees, even some on Cyprus.

And they. They're public enemy number one to commercial foresters because they take a beautiful Christmas tree with all the straight board feet and, whatever units of timber you want to use and turn it into this contorted structure that can never go through a saw mill. And so there's been tens of millions of dollars of research done on mistletoes courtesy of the US Forest Service to try and find a weak link, a little chink in the armor of this pernicious parasite.

So the dwarf mistletoes of the US have been very well studied and by extension looking at their relatives in in Mexico. Australian mistletoehave been quite well studied in terms of their ecosystem impacts. And just now we're starting to see some really good work being done in many parts of Africa and many parts of Latin America, quite often by homegrown researchers in those regions either studying them as, as entities in their own right and learning out new stories.

Like there's a, the first bat pollinated mistletoe was just described in Brazil a few years ago. [00:09:00]  But also seeking to test these ideas that have come from other systems and see if it applies in a novel ecosystem. But surprisingly, not just among mistletoes, but in parasitic plants more broadly the few really detailed ecological studies that have looked at these plants and how they fit into their world.

Remarkably congruent in their findings. And it's it's the exact opposite of the effect that it has on the host. So we spoke at the start about how parasites make a living by taking from others. That's what makes the mistletoe. And so obviously there's been some studies showing that trees and mistletoes have slower growth rates.

They may be more susceptible to drought, they may be more susceptible to, to, to dropping branches prematurely, surprisingly, very little. Evidence, direct evidence for mistletoes affecting mortality. And every study that's looked at that has found it's often indirect, like a tree with mistletoe might get more beetle damage, and that's, that pushes it over the edge.

Or a tree with mistletoe might get more fungi coming in through those connections. And [00:10:00] that then leads to, to, a fatal disease. But in terms of the ecology of not just the tree and the things on the tree, but the neighborhood around that tree, the stand, the woodland, the forest.

There's been some, a few studies done on that in Europe and North America. My own work in Australia. And it, it shows that sure, they take from their individual infected host, but then they give and they give really freely. They're one of few groups of plants that relies on animals to both pollinate their flowers and disperse their seeds.

So they bribe freely with carbohydrate rich nectar and amino acid, rich fruit. With a fruit, it's quite often for a specialist consumer 'cause it's a sticky thing. It's quite hard to process. And it's very reliable. So you have all these different birds around the world that have worked out.

If you can find mistletoe you will never go hungry again. 

[00:10:52] Michael Hawk: On a, sorry interrupt. I recall on a trip I had to Australia, actually, there's actually a bird called a mistletoe

[00:10:58] Dr. Dave Watson: The greatest bird in the 

[00:11:00] world.

So, so there's those partnerships with pollinators and with seed disperses, I. But also we see the way that the parasitic plants draw water from their ho, from their host, which is really important. If they can't do that, then they die, within minutes. They don't do it actively, they do it passively by retaining very high concentrations of nutrients in their stems and leaves.

So they're full of salts, of goodies. And they use that concentration to pull to, to passively pull water from the host as the water tries to equilibrate across that that gradient between the two plants it's effectively like osmosis. And then when the plant is done with its leaves they churn through their leaves quite quickly.

 They drop their leaves with all of those nutrients still in them. So. Parasitic plant litter, leaf litter and mistletoe leaf litter in particular can have 17, 20 times the concentration of potassium as the host. Many metals that are quite rare in [00:12:00] soils and, herbivores have to work really hard to find to get a complete diet.

It's just loaded in mistletoes. And so that's one of the reasons it's such popular food. So many browsing herbivores will go out of their way to eat mistletoe. Not really as a main meal, but just as a, like, almost like a vitamin just to get all the bits and pieces they're missing. All the great apes go out of their way to eat mistletoes.

It's one of those things. But then they drop it as a steady stream of enriched litter and that. That's like crack for a forest. It just goes bananas. All the microbes and the fungi and the soil that are limited by particular nutrients suddenly have unlimited nutrients. So decomposition rates go sky high carbon assimilation rates increase the porosity of the soil, increases invertebrates, move in, mopping up all these tasty fungi and then insectivores.

Follow in, in hot pursuit of the insects. So worldwide we see in areas with more mistletoes, like two comparable forests. [00:13:00] One's got a few mistletoes, the other one doesn't. There'll be more species of animal in that forest. Some of it is with a mistletoes. Some of it will be because those connections 'cause they eat mistletoefruit or because they need mistletoe nectar.

But most of it, it's through that brown fruit web from the lizard to the insects to the insect of wares. And insect of wars are one of the most dominant groups in most forest communities. , so yeah, they might take from an individual host, but they give back to the entire ecosystem. And if you look at where those nutrient inputs occur, it's within the feeding zone of their host.

So the host gets those nutrients back, it just rents them out to the rest of the ecosystem for a little while.

[00:13:38] Michael Hawk: Yeah that's really interesting to think about because I am thinking about adaptations of, say, desert plants where nutrients and water and. Soils tend to be very porous and low nutrient. So a lot of times they have adaptations that allow them to retain their leaf drop and cycle that back into the soil.

So, oh yeah. My mind is going [00:14:00] wild with all the different hypotheses that that one could come up

[00:14:03] Dr. Dave Watson: Yeah. And all of it comes down to the fact that they're parasites. So different rules apply. They didn't work hard to get all those good things, and so they're just gonna drop them because they know there's more coming down the pipe.

[00:14:15] Michael Hawk:  that process apparently, as you said, doesn't hurt the tree enough to kill it. So that recycling is perhaps part of that process that keeps the tree going with better soils or more um, spongy, soils that can hold water.

[00:14:29] Dr. Dave Watson: Exactly. And some Spanish colleagues found that, not just that, but the birds that eat mistletoe fruit eat other fruit and they bring in those seeds as well. So if there's a, if there's a tree with a few mistletoes in it, you're gonna get more fruit bearing shrubs in the understory in a few years.

[00:14:44] Michael Hawk: Yeah. So I mentioned the mistletoe bird, and you were talking about seeing a lot of bird diversity near mistletoes. Beyond eating the fruit and then dispersing the seeds, are those birds eating the leaves in situ or are there other things going on [00:15:00] too?

[00:15:00] Dr. Dave Watson: sure. So leaf eating is quite rare in birds. There's only a handful of birds that do it. There are a few birds that eat mistletoe leaves. But none in a really, so there's turacos in Equatorial Africa. There's the plant cutters in Patagonia. There's a few weirdos that do it. But from a bird point of view, nectar and fruit are the two big ones. But then nesting there's a, an a startling variety of birds preferentially nest inside mistletoe clumps. So if you think of your, a cartoon tree, just a generic tree, it's pretty open. It's got a crisscross network of branches in there. And then a a canopy of leaves.

And different birds have worked out ways of affixing a nest to that. They might hang it from a branch. They might put it inside a fork. They might stitch some leaves together. But mistletoes are like a compressed tree. They're more branched and the leaves are semi succulent.

They've got a very high amount of water in them. So in a dry area or in a windy area, in a very hot area it's measurably [00:16:00] cooler inside a mistletoe clump than inside the rest of the tree. And many birds in all parts of the world will seek out mistletoes as a structure within which to place their nest and a microclimate within which to to raise a family.

So, and you see that worldwide, like Cooper Hawks, a, a bird that'll be in your backyard. They almost every Cooper's Hawk Nest described is in a mistletoe.

[00:16:21] Michael Hawk: I did not know that. And I do see them a Excellent. Well, now you know where they've come from.

it's a good indicator. Yes. The thing that has always been interesting to me about birds that nest in mistletoe is that. It is a hotspot for a lot of activity, a lot of other birds. So I'm wondering, how do you reconcile a bird choosing to nest somewhere where there's like all this extra attention from other bird species coming in and maybe other mammal species as well coming in?

[00:16:50] Dr. Dave Watson: Yeah, so that we tried to capture that. It was the we've looked at that specifically in a few cases. And I think the title of one of our papers were cafeterias are a lousy place to [00:17:00] raise a family. Because of just the, what you're pointing out, typically it's seasonality is your friend.

So that when there's peak fruiting or peak flower availability that's not during the breeding season of these birds. So it's not as if they're having to bother. But a lot of the missiles we're talking about are quite large and the fruit and the flowers are born on the ends of the stems.

Whereas the nests are quite often on the connection, on the house story between the mistletoe and the host or right within that network. And that might be a meter away from where things are coming and going. So I think you can have, I think you can have both without too much troubles.

 But certainly some predators will keen on that. And so there's counts of African lizards, of various birds of prey. Hiding in and around mistletoe clumps waiting for birds to arrive because they know it's just a, it's a center of activity.

[00:17:45] Michael Hawk: what else comes to your mind when we think about the ecosystem impacts of mistletoes?

[00:17:51] Dr. Dave Watson: Yes there's two things that are tickling my fancy at the moment. One is, one is climate change stuff and the other is history. And we've spoken a little bit about both, [00:18:00] so. I mentioned that lots of things nest in mistletoes because they're they're a dense structure and they're, they've got that high moisture content of their leaves.

There's a bit more to it than that. And so we've done some work now showing that at the whole of tree scale a tree with mistletoe in it is measurably cooler than an otherwise similar tree. And there's a reason for that. The stomata, those little holes in leaves where gas exchange occurs.

The way plants regulate water loss is there's two little cells either side of the stomata called guard cells, and when there's lots of water in the tree, they close and the stomata is closed up. mistletoes can't close es their leaves are always open. They are always bleeding moisture into the world and so on.

[00:18:42] Michael Hawk: That goes back to the sort of the osmosis comment.

Yeah. 

[00:18:45] Dr. Dave Watson: they're just always drawing and always releasing water. And so in very hot, very dry conditions, there can be a 10 degree difference of a mistletoe infected tree as opposed to a regular tree right next door because of that just dripping [00:19:00] tap effect. And so if we're thinking about street trees and cities, we're very concerned about urban heat island effects.

Cities have lots of hard surfaces that, that store heat. And anything we can do to add green space to our cities we know helps. But adding mistletoes to street trees in our cities, I think is a next level strategy that I need to I need to, get on a global campaign to to make that happen.

[00:19:23] Michael Hawk: Is this something that, that could efficiently be done by people? Because I guess if a bird comes

along 

[00:19:28] Dr. Dave Watson: we've, yeah, we've done it. We've done it. It can be done. I'll send you the paper. And look, the other thing that, that, that really gets my flips, my pancakes is the, is how long has this bird mistletoe dance been going on for? So I mentioned that mammals got the party started a long time ago.

But just recently I reviewed a lot of what we know about early bird diversification and early mistletoe diversification. And it looks like they tracked through the same places at the same time, certainly in Latin America. [00:20:00] So when some of the main lineages came into Southern South America from the south, from Antarctica, as Gondwana was splitting up, it looks like mistletoes and birds basically hitched a ride on one another and leapfrogged right the way across the Americas.

And so working that out is gonna occupy my mind for the next year or so.

[00:20:19] Michael Hawk: The other maybe crazy, ill-informed thought that came to my mind is, here in California we have the coast redwood trees, which are just these immense trees and they can have ecosystems in the canopy where different plant matter accumulates, A bird comes along, it drops a seed, and you can have shrubs not parasitic shrubs, regular shrub just growing up in the canopy.

so that has me wondering like, is this a ripe area for new mistletoe to emerge? Because, you have this kind of alchemy going on, way up there in the canopy.

[00:20:52] Dr. Dave Watson: Yeah, for sure. That's where amazing things happen and there's some very clever epi fight researchers that, that are looking at those sorts of things. And the way, regular [00:21:00] plants grow in that system, they can grow roots outta places that they normally don't grow roots from.

And you get crazy animal communities up in there as well. Tardigrades go bananas in coast. Redwood epithetic gardens,

[00:21:11] Michael Hawk: we've been talking a lot about mistletoe on trees. Do you ever see mistletoe, again, it's a fuzzy definition, like what is a tree? But do you see mistletoe on other plants? Smaller plants?

[00:21:21] Dr. Dave Watson: Rarely. And there's, I mentioned those two main groups of mistletoes that account for the vast majority of them. There's the Loranthaceae, which is a southern derived Gondwana derived group. They're the ones with the. The bright flowers, they're often called showy mistletoes. And then there's the Visceae, which is originally from Laurasia.

They're smaller flowered. And that's the Christmas tree mistletoe that's that we tend to think of. And the earliest branches of one of those families, the Loranthaceae, , their root parasitic mistletoes. So they were mistletoes before there were trees to infect. So we are talking 70 million years ago or so.

They popped out. So ancient beasts. And they'll infect anything. [00:22:00] So they'll send out roots, almost a hundred meters in any direction. They'll infect carrots in your vegetable garden. They'll latch onto anything they can find. And there's actually a real issue around Perth, where they grow that they'll find cabling used for telecommunications, fiber optic cable. And they'll the roots just assume it's some strange route that they've never encountered before. Wrap around it and slice it in half. They've got a hydrostatic guillotine that can just cut through anything. And so you're there having a chat with your friend.

And suddenly internet goes out mistletoe,

[00:22:32] Michael Hawk: I, that one really hits close to home because I spent many years working in the , telecommunications industry, and fiber cuts were a big deal, and very often hard to locate. But I don't ever remember having to locate a mistletoe induced fiber cut. Usually it was an animal or a root of a tree, or more likely an accident train derailment or, something like that dug into the earth.

So, wow. So you've peppered this [00:23:00] conversation with a number of tidbits about the research in the papers that you've written. I'm curious if you have anything else you'd like to say there. Do you have any other uh, discoveries or research findings that you'd like to share or maybe something in progress that we can look forward to?

[00:23:14] Dr. Dave Watson: Sure. Yeah, there's a lot of what I've spoken about was directly from work I've done or I've done in collaboration with colleagues in terms of where things are going. I hinted at this in the history bit. Yeah, so it looks like the group of, let me leave you with this.

 The most diverse group of birds in the world got that way because of mistletoe. So the tyrant flycatchers and their allies is a group of just hundreds upon hundreds of species. That'd be familiar to many of your listeners as King Birds and Peewees, all those distinctive fly catches you see in the us.

 But then you go to South America and there's 101 versions of them, and then there's the tings and the mannequins and all their little friends. They rode the mistletoe wave coming all the way up from South America [00:24:00] as those plants moved into the forest and added a regular source of fruit and a regular dripping tap of high nutrient leaves.

Those frugivores and insectivores came up there with them. So that's a massive preview of about three papers that are gonna be published in the next two or three years. In terms of other stuff oh look, there's just so much. I think I'll just leave, I'll leave it with that one.

[00:24:24] Michael Hawk: Next we'll dive into a conversation that opened my eyes into just how interconnected and vulnerable our ocean ecosystems really are. I spoke with Dr. Judith Gobin, a recently retired marine biology professor from Trinidad and Tobago, who spent her career studying everything from shallow coastal waters to the deepest parts of our oceans.

What struck me most about this conversation is how Judy reveals biodiversity operating at scales. Most of us never consider. First, you'll hear how mangroves, seagrass beds, and coral reefs aren't separate ecosystems at all. They're intimately [00:25:00] connected in ways that create some of the most productive environments on earth.

Then Judy takes us on an expedition 3,500 meters deep with Robert Ballard. Yes, the Robert Ballard, the one who found the Titanic In this case, they discovered cold methane seeps supporting entirely unexpected forms of life, including nearly 200 potentially new species.

But here's where it gets urgent. Judy explains that beyond 200 kilometers from the coastline, the ocean floor is basically unregulated territory. Right now there's a race between deep sea mining companies who want to extract minerals with what amounts to underwater bulldozers and scientists trying to ratify a new treaty to protect these ecosystems .

What you're about to hear isn't just about discovering new species. It's about understanding that what you're about to hear isn't just about discovering new species. It's about understanding that what happens in the deep ocean affects all of us, whether we live in the Caribbean or thousands of miles [00:26:00] inland, the ocean's connectivity means nothing stays isolated and the clock is ticking.

Let's listen.

I think a lot of folks are pretty comfortable with terrestrial systems. We we can talk about different types of forests or wetlands or, or things like that. But you know, we aren't so familiar with those in the ocean because they're kind of beneath that glassy sheen of the water and we don't see them and interact with them

all the time.

So could you maybe provide a quick overview? You could start with the systems that are in Trinidad and perhaps move more broadly beyond that some of the more productive or biodiverse marine ecosystems that are out there.

[00:26:42] Judi Gobin: Sure. So just let's remind our listeners the location of Trinidad and Tobago. So we are the southernmost islands of the Caribbean, a twin island state, Trinidad and Tobago, southernmost. So we are [00:27:00] actually at the tip of South America. We are very close to Venezuela and of course, and as I mentioned, South America.

So. The reason I mention that is that we are actually in a very unique position, meaning that we are not totally oceanic because we are influenced by outflows from the Orinoco River in Venezuelan South 

America. So it's it means we're not, we haven't got the blue waters like one would expect, but we do have it as you go further north.

So that's why when you go further north and starting with our. Our twin, Tobago, which is really more of what we would consider to be our tourist island. That's why you have the proper oceanic reef developed there. It's the Buccoo Reef, and it's very well known worldwide, [00:28:00] I believe. We still have on record one of the largest brain corals located there.

And it's wonderful diving. So Trinidad and Tobago has a bit of both, as I may say. We're in a unique position. So we do have a coral reef, which most listeners would appreciate. We have the variety of fish, biodiversity of organisms reef organisms. You name it, we have got it. And of course, The one thing about, tropical islands, it's, of course, it's all very colorful, the sponges, the corals, the fish, the variety.

So very colorful, very typical of what you would see in a textbook or in a some marine aquaria and so on. The ones that you can't so you dive and you snorkel, you're able to see what to reveal what's in the coral reef system. What is not as easy to see is, of course, as you go from your beach, sandy [00:29:00] beach into the water in the intertidal as you're walking in.

You don't see the interesting organisms that are there. So our sandy beaches are rich. in biodiversity. So these are where you get all the burrowing shells, the bivalves, you get the tiny crabs, you get the there's small intertidal fish as well, which kids, as kids, you try to pick from the water when you go swimming and things like that.

And then you move out into the, so you can have a seagrass bed. So we have, the seagrass beds tend to be often found. Proximal to the coral reefs system and often proximal to the mangrove ecosystem as well and wetland system. So, for example, in Buccoo Reef in Tobago, We have all three ecosystems literally next to each [00:30:00] other.

, and again, the wetlands are, they would be, there would be an estuary that brings the fresh water to the sea. And that, of course, makes it the mangrove system, the ecosystem. It's that mixture of the estuarine runoff flows from the terrestrial environment and coming in a river, of course, and where it meets the marine environment.

And you can imagine the productivity and the sort of richness of the productivity, and that is why that area where the mangrove meets the seagrass beds, the seagrass beds reach, meets the coral ecosystems, you can understand and appreciate why it is so productive and diverse because the organic material that's being brought by the estuarine system feeds and, this system, which is, sharing all of these [00:31:00] rich resources in places like Trinidad and Tobago.

So, for example, our huge, we have very huge wetland systems. One of the larger ones is the Nariva Swamp and or the Caroni Swamp, and they are extremely interesting areas most, people who have never been, they think swamp, it's muddy, it's murky, you can't see what you're stepping into but it's, it's really quite interesting and attractive.

[00:31:32] Michael Hawk: And are these saltwater swamps or brackish

[00:31:35] Judi Gobin: Right, so these would be brackish water. So some parts of course, the, the sort of more terrestrial areas are going to be more fresh water. Then you get into the estuarine and then you get into some areas which can actually be quite salty. And that's where in the sort of saltier waterfront area where you get into the seawater now, you will have the [00:32:00] more salt tolerant plants and animals as well.

So you'll have Mangrove plants that are more salt tolerant on the outer part of a mangrove wetland or of the wetlands where it's actually now in seawater, basically, so the richness of these environments and the support you have crabs and the shelled organisms, you have mussels, you have a lot of waterfowl, a lot of bird species, and in Trinidad and Tobago, our national bird is the The Scarlet Ibis and the Caroni Swamp is well hopefully lots of our listeners are going to recognize that it is an extremely very wonderful place to visit to see thousands of scarlet ibis as they are roosting when they come in the evenings.

They come in around five, six, six o'clock in the evening. They, they fly off during the morning period and they come. So [00:33:00] that's when we have the tourist boats going down into the swamp because the green mangrove trees are dotted with scarlet ibis. So they basically look like, thousands of apple trees with just red dots on them.

And of course, close up, that's the whole exciting part of the tourism activity where you can actually see them roosting.

[00:33:23] Michael Hawk: So just kind of for, for my benefit, comparing these systems to terrestrial systems I know that And this is sort of what you were describing. So, so perhaps I'm just repeating in a different way, what you said, but ecotones. So if you have two different habitats that are close to each other, we call that an ecotone and they're often very productive because you're 

getting, you know, two different systems interacting and potentially 

twice the number of resources in close 

proximity. So is it kind of the same concept

[00:33:52] Judi Gobin: Kind of The same concept and, and that's what makes the marine environment so rich because you're having not just [00:34:00] this sort of seawater that's circulating and coming from different areas and different wave patterns and different oceans, movement of water, but you are also having the terrestrial input.

And that terrestrial input is very rich in organic material. You have, remember you're having break down of carbon material from trees and animals or being transported via the estuaries, passing through the mangrove systems and getting into the sea and then, of course, the associated seagrass bed or the coral reefs.

[00:34:34] Michael Hawk: Maybe you can tell us a little bit about what it means to be a benthic ecologist and how that led you into the deep sea systems.

[00:34:41] Judi Gobin: Sure. So as a marine biologist, marine scientist at the university, I was engaged in a lot of benthic ecological surveys. And those are basically you look at marine organisms that are living in the sediments. These are the, and lots [00:35:00] of. Listeners may not, they may think, Oh my God, what's there? But you have some of the most interesting organisms there.

You've got polychaetes, you've got nematodes, you've got crustaceans, you've got fish and, and, diverse environment. And when you think about it, it's a very. In extremely productive environment, meaning it's that part of the food chain where all of your other animals are feeding off of. So it's the base, really, of the entire food chain.

So my benthic organisms, although you look under a microscope and you spend days and days trying to identify what are these little worms. What are these little organisms? What are these nematodes and gastrotrichs and all the various things? Copepods and so on.

Why are they important? They're important because they're the food source for everyone else up the food chain. And if they go missing or if they are [00:36:00] negatively impacted, as they often are with drilling for oil, drilling for natural gas deep sea mining rather just mining in the ocean and so on.

So negative impacts or destructive activities can wipe out the food source for a larger number of organisms. So we're not going to be able to have the fish that we're accustomed to having. And , this is actually one of the reasons why there's been a decline in the fisheries, because a lot of the exploration activities have negative and other activities have negatively impacted on the benthos or the benthic systems.

And the study of benthic ecosystems is. really part, I'm very pleased to see, it's a major component of environmental impact assessments across the globe. So, we were very pleased that it was included and it has to be included in marine [00:37:00] environmental impact assessments. that then led me to As part of those studies and my collaboration with colleagues, I was invited on the exploration vessel, E. V. Nautilus, and it's owned by Professor Robert Ballard. And Professor Robert Ballard is well known as the, the marine archaeologist who was responsible for locating the remains of the Titanic.

He has really just kept his interest in marine archeology , and marine biology and biodiversity. And this exploration vessel as opposed to a research vessel. The exploration vessel is all about exploring different areas. And we were very fortunate in the Caribbean that the vessel was coming to Trinidad and Tobago rather it came to Grenada first, in 2013 and a year later in 2014 came to Trinidad and [00:38:00] Tobago.

 I was on that vessel with Professor Robert Ballard. And of course, I guess that's the highlight, one of the highlights of my career. What was also very interesting, of course, is in the textbooks, As a marine scientist, a marine lecturer, I had noted that there were certain seeps, cold seeps that were present.

That's where the, it's, it's in the core of the earth where there's release of gases coming out from the, the core of the earth. And there, some of them were located in our deep seas and it's so they're, they've been on maps and they looked pretty close to Trinidad and Tobago and Venezuela and South America.

We stumbled upon the seeps and they are cold methane seeps that we were now able to see really in action. And we have [00:39:00] those documented in some lovely videography, which we can share with podcasts.

listeners who are interested, but it, it really was a first for Trinidad and Tobago and the Caribbean. And we, on that expedition, and that one was in 2013, we discovered muscle, Bathymodiolus muscle, that was the largest on record. So we have the largest muscle on record, Bathymodiolus species and that's from Grenada.

So we we were very chuffed that here we were, we were able to uncover new treasures that were basically in our backyard in the Caribbean. And so it was the start of an amazing foray into the deep sea.

[00:39:48] Michael Hawk: That mussel that you found, is it only then only found near that volcano?

[00:39:54] Judi Gobin: It's not, it's not actually. So it wasn't a new species, but it was [00:40:00] we know that they are present in areas under those similar types of conditions. But it, it was the largest one on record and, but, but following , your train of question I'm very pleased to tell you that our 2014 expedition off of Trinidad and Tobago and other parts of, of the area,

we have, we have collected close to 198 I'm very pleased to tell you that our 2014 expedition off of Trinidad and Tobago and other parts of the area, we have, we have collected close to 198 potentially new species of organisms and I'm going to pitch in here that one of the ones that's been described before is actually named after me.

It's called Lamellibrachia judigobini. So any of our podcasters interested look for

[00:40:51] Michael Hawk: I will definitely do that. And I'll link to what I find in the show notes so that people can find that.

[00:40:56] Judi Gobin: So really the, the, the, the point is the, the [00:41:00] sort of excitement about all of this was we are still in 2013 and, and even up to, and 14 and, and now certainly we are still discovering new species in the deep sea. And this is why. We recognize deep sea as being extremely important.

Sure. We knew that our marine ecosystems, as we've talked about earlier in this conversation, we've talked about how very important they are, and especially for small islands, states like ours that rely on the ocean's productivity to basically feed its people for our tourism, for communities livelihoods, shipping, transport, oil and gas.

as well. Now we are recogni Of course, it's just as important and the deep sea really is quite, it's another very large ecosystem that is, is one [00:42:00] that we hadn't quite considered in the equation before I mentioned professor Robert Ballard and The, the really, this whole discovery of seeps and so on has really only happened in the last 45 years or so.

So the interest and the, the sort of building of knowledge and capacity in deep sea biology is still fairly young. But having said that, we have learned quite a lot about the deep sea, and we know that, of course, the deep sea, like the other ecosystems we've been talking about, It's not barren. There are, there is a huge biodiversity of organisms as we revealed in our deep sea for Trinidad and Tobago and that's just really the tip of the iceberg.

There's that very important element that we need to consider and it's The use of some of these organisms for extraction [00:43:00] of products. And this is what we call or refer to in science as marine genetic resources.

Marine organisms and the marine environment is the last frontier. We are still discovering marine organisms. We are also, these Resources or the genetics, the sort of DNA material and so on that we extract from them are what's used in a lot of cosmetics, pharmaceuticals, cancer, drugs enzyme production, foods, and so on.

[00:43:33] Michael Hawk: if you're speaking to somebody who maybe unaware of the importance and also challenges faced by deep sea, how might you describe , those two related aspects?

[00:43:45] Judi Gobin:  So small islands. States or SIDS. Recently this whole conversation about deep sea biodiversity and protection of and conservation of biological diversity has [00:44:00] come to a head in Discussions of a new treaty called the Biodiversity Beyond National Jurisdiction.

And I see it as a, and a lot of us marine scientists, see it as a landmark treaty. One that we we are very, very pleased about because there's, it's what I consider to be a science based treaty, because there's now , this real and genuine link between science, what we know, and how we want to conserve and protect it.

 So to put it into context, you have in the outside of national jurisdiction. So this is not in our, our territory. So this is outside, let's say of Trinidad and Tobago's national jurisdiction. 

[00:44:49] Michael Hawk:  If I could pause you on that, like when we think about national jurisdiction in the ocean you can almost imagine, and I'll have to look it up, but there's a perimeter that extends [00:45:00] from the land, a certain number of kilometers, basically

[00:45:03] Judi Gobin: It's, it's 200. 

It's 200. 

[00:45:05] Michael Hawk: And then all of space outside of that. So you imagine a globe and then extend.

Open ocean. can anybody kind of do whatever they want in

[00:45:14] Judi Gobin: That's right. It's called, it's, it's, it's basically falls under the, the rule of law, the common heritage of mankind. So you're free to go there. You're free to do whatever. And the, and of course, a lot of the shipping and transportation routes.

fall outside of national jurisdiction, that is the areas that are an island or territory may be responsible for. And so what has happened now, of course, with development and with all of these exploration, the deep sea being the last frontier, as I mentioned, for obvious reasons, they are rich resources, they are untapped resources.

resources. And there are these resources which, which have been, we know are present, they've [00:46:00] been documented. We know a reasonable amount about them. These are like polymetallic nodules. These are, the other minerals, diamond, copper, and a lot of these minerals and components are what contributes to mod or what they make up parts of new technologies, our computers, our phones, and so on.

And the demand, of course, is great. Very great. So, countries are already applying to the International Seabed Authority, which is actually the authority base. It's the institutional basis in actually in Jamaica And. You have to apply, all the states and countries have to apply to the International Seabed Authority for extraction licenses to go into the deep sea now, [00:47:00] to mine for these materials.

[00:47:02] Michael Hawk: And that's as a result of the new treaty

[00:47:05] Judi Gobin: no, are very fortunate that the treaty has come at the right time because there were exploration requests so from, you have countries that are able to go out and explore because it's quite costly, of course, for the deep sea mine for these materials., It's quite expensive. So , they've been these exploration requests to the international seabed authority. And. Exploration activities have had begun even before the treaty came into, well, the treaty is a new treaty, but it's not in effect just yet until parties have signed on and so on and ratified.

So we're at that stage now, but we are very pleased that the treaty is hopefully going to be ratified before any one of [00:48:00] these activities, actual deep sea mining takes place. So there's been exploration going on and it still is going on. A lot of the territories have joined together to request that there be no further exploration activities, that there be no deep sea mining.

You'll see it's very topical. There's the conversation of pro deep sea miners and, and anti deep sea mining. As a scientist, of course, we like to consider that we have very balanced opinions, and I started this off by saying that the trea the treaty is science based, and I think it is very important for us to consider that we would, we should really not destroy before we have a really good idea and document what is actually out there.

So we're talking here, when you mine in [00:49:00] the deep sea, it's not just going out on a vessel and picking what you want. Through, with the use of an ROV or, sampling in some other way. This is picture a bulldozer at this depth, we're talking 3, meter, just trampling through and taking everything in its path.

And that's really what we object to. This is really quite destructive. We are already aware that there's been, there are negative impacts of oil and gas exploration activities. There's always releases, there's always contaminants, there's pollutants, and they affect oil on the sediments, the benthic organisms that I looked at, some of them were covered in oil.

Often there's a sort of, it goes, some systems are abiotic where everything dies off when you have the activities going on, or for a short period after. Sometimes they recover seven, [00:50:00] eight months later, but of course it's never back to what it was. In the deep sea, we have no idea what's going to happen because we, we, It's not like we can experiment or we can do a survey at the moment, but what we do know is the machines that are being used are so destructive that they are going to literally be destroying everything in its path.

And that really is the aspect that we're very we want to bring to the fore that let's take a step back. We want to ask, the industrialists, we want to ask those who are thinking about it, those with, the money, to finance these activities. Let's take a step back.

Do some more scientific studies and then come up with proposals pretty much like you would do for an environmental impact assessment in the deep sea. Unfortunately for us, the biodiversity beyond national jurisdiction, the treaty, [00:51:00] there are sections and one of which is environmental impact assessments.

One is capacity building, and I did allude to that. earlier where the small island scientists like myself, we want to be involved in this conversation because what happens in the deep sea is going to affect our islands. It may be outside our national jurisdiction, but the ocean is connected and that connectivity is, it means negative impacts can come into our systems and we can feel the brunt of that.

So we need to be part of the conversation. At the same time, as I mentioned, with the development of drugs and so on, and pharmaceuticals that are now on shelves, cosmetics and so on, that are in use, that will have a label that says it came from a Caribbean sponge. Or Caribbean coral, Caribbean scientists would like to be involved in that process.[00:52:00]

And the BBNJ treaty does actually specifically state that there must be capacity building in areas where these kinds of activities are taking place.

[00:52:12] Michael Hawk: So you mentioned that the treaty still needs to be ratified signed off. Who, who is driving this effort and, and what is the outlook? How long do you think it might be before we

do get to a ratified state? 

[00:52:25] Judi Gobin: we, are aiming, to have all the signatures for, so it's the United Nations and so you just, you could just go online, look at the United Nations the treaty, and you, by, by I believe it's the end of 2025, we must have a certain number of signatures. So the numbers for it to, and then for it to move to be ratified and so on.

So we are hoping. That they, we will get the numbers. 

[00:52:53] Michael Hawk: You said you're hoping that you'll get the numbers. is there some question as to whether that will actually occur?

[00:52:59] Judi Gobin: Not so [00:53:00] much that be where there's been very, very good support and very good interests, but there's of course in some first world countries. They, of course, they're the ones driving the, the need and the request , for deep sea mining.

that and the demand, of course, so they are not going to jump to sign on because they want to carefully have, conversation, they want to see what's going in all the annexes and things like that, how it's going to affect their activity and the process.

[00:53:35] Michael Hawk: And coming in early 2026, we have a full length episode with Natalie Hernandez. She's an entomologist who specializes in aphids with 4,500 species worldwide. That's certainly an underestimation. These tiny but amazing insects often give live birth, and they're a critical part of the food web.

Many species are a specialist that is, they only eat specific [00:54:00] plants. They help support ant colonies, our host to parasitic wasps and our food for many other organisms. Some are even quite colorful. I find them endlessly fascinating. So please enjoy the sneak peek at one of our upcoming episodes.

One of the reasons I wanted to talk to you is, is aphids, I, I sometimes call them and, and I later found that Doug Tallamy uses a similar analogy.

I used to think I came up with it myself, but I probably heard it from him that aphids are kind of like the, the plankton of land, because they, They fulfill an important role of like converting plant energy into, energy that other animals can use in the food web.

And I think we'll get into that here with, if we talk about the life history, . Just tell me like at the highest level, what is an aphid.

[00:54:48] Natalie Hernandez: So the aphids are I, they're also called plant lice because they have sucking piercing mouth parts. They're gonna insert those sucking, piercing mouth parts. They actually have a little straw inside that they can [00:55:00] weave between plant cells. 

It's like just a little clear, very long tube that they will weave into the phloem of the plant. And so they are phloem feeders. There's also a lot of related hem trins that are xylem feeders. But because they're phloem feeders, they've developed this specific CH filtering chamber in their digestive system that allows them to soak up the phloem, which is the plants, pretty much like the plant's blood, but it's very sugar heavy.

So what they're after is nitrogen. And so they suck up all of this phloem and then they're filtering out all those sugars in all the water, mostly trying to get nitrogen and then other minerals and chemicals that are in the flow that's gonna help them grow. So then they excrete pretty much sugar water as poop, and that's what they're doing sitting on these plates.

They're just soaking up all of the sugary substance, excreting sugar water poop, which is called honeydew. Someone decided to try and give it a cuter name, and then that's why you see a lot of other insects that come and [00:56:00] interact with them like ants. A lot of people are really interested in the ant aphid relationship, or very surprised by it when they see, they post pictures and they're like, what are these ants doing?

Are they eating the aphids? And then I explained 'em like, no, they actually tend aphids for that honeydew. And so there's not a whole lot of insects that produce honeydew the way they do since they're, a lot of other insects are xylem feeders, which is more water heavy, not quite as much sugar, so it's not as sweet.

But ants will attend related insects too, in the same way just trying to get some of that sugar water. they're kind of their own distinct group because they're the only insects with chronicles or sunk the two little tailpipes on the back end. And not all aphids have Cornicles or Siphunculi, though, I call them Siphunculi.

A lot of other people call them Cornicles, and if you see Cornicles or Siphunculi, it's definitely an aphid, but not all aphids have them, if that makes sense.

[00:56:58] Michael Hawk: What [00:57:00] function do those parts serve? Is that where the honeydew is excreted.

[00:57:03] Natalie Hernandez: The honeydew is actually from between. The tailpipes, the, the Siphunculi excrete, alarm, pheromones and wax. So when you see a colony sitting on a plant, if they're disturbed by a predator, they're kinda like, the Cornicles are kinda like smoke stacks. So they release these alarm pheromones, alerting the rest of the colony that there's a predator nearby.

And then you might see little globules coming out of the tips of the Siphunculi, which is wax. So if a predator comes up and bites them, it's gonna gum up their mouth parts and make the a, it make it more difficult for them to eat the aphid.

[00:57:38] Michael Hawk: All right. I hope you enjoyed this quick look at some of the biodiversity topics from last year, as well as the sneak peek to what's coming up next year. Thank you so much for listening to Nature's Archive throughout 2025, and we look forward to bringing you many more great nature topics in 2026. Happy New Year.