Marine-fuelled Ecosystems in the Great Bear Rainforest - Dr. John Reynolds

Added: 2026-06-03

[00:00:00]So, we're so happy you're here for the first one. A couple announcements before we begin. I'm Grace. I work in the whale lab, the lab with the whale on it and the touch tank. You probably walked past a hundred times. You're always welcome to come in and say hi. Uh I work primarily with the field trips department. So, doing our educational program development, doing things like conferences and workshops, and I get to do like all of our fun events like summer seminar series. So, you may see me in and around around town about town.

[00:00:28]Um This week is also ocean week. It's ocean week here in Canada from the 1st through the 8th. At the MSC, we're hosting three events. The first one is right here right now. You've made it.

[00:00:39]Congratulations. Tomorrow we are hosting a beach cleanup at Pacina Bay. Uh you're will folks who are interested to meet us there.

[00:00:50]>> Keep going. Just just hold it if you want.

[00:00:53]>> Um we're hosting a beach clean up tomorrow, Wednesday at 5:00 p.m. at Tina Bay. just 10 minutes down the road.

[00:01:00]We'll be parking at the campground side, so the the Pacina Bay campground side rather than the National Park side, but you'll we'll see on the beach. Kirsten and I will both be there and we'll be in our high vis bags and gloves provided and it'll just be a gorgeous evening on the beach taking care of the places that we spend all our time. Then Thursday is back here 700 p.m. Same time, same place, but different speaker. I'm actually our speaker for Thursday. I created like a very silly fun interactive talk on the deep sea and like we'll like point and stare at all these amazing deep sea creatures and talk about how protected and just all the crazy stuff going on down there. So you are so welcome and would be u greatly um appreciated your attendance.

[00:01:46]You're so invited.

[00:01:48]Okay, our speaker tonight is Dr. John Reynolds. Many of you are very familiar so I'll actually just invite him up. We are so grateful for you sharing your talk this evening. Thank you so much for being here and thank you all for attending. Please welcome your nice sunny game of the Stanley Cup. This is no looking at your phones.

[00:02:16]>> It's okay. It's particularly impressive here. Um, so yeah, I'm happy to talk about some of the more well given that it's a game. Uh, so I'm going to talk about our work on um, we've been doing for a long time um, up in the Great Bar rainforest. My my position is technically it's a leadership chair in salmon conservation. And so I when I was first setting this up trying to figure out what it would look like, I got very interested in the story about nutrients from salmon by supporting other components of the ecosystems. Um but anyway, very keened to um give a talk about that. And also by the way, if you ever want to u find me um I'm just here in the top of the leaderboard, in case you're wondering, I expect to be displaced after I leave. Um right, so with a lot of people tend to specialize on one type of habitat and many people habitats differently. So here we have an estuary. Out here we've got the ocean of course and people would look at this in very different ways. Terrestrial ecologists for example I said with the water if they can avoid it they have their own internist their own meetings their own conferences their colleagues and so on. So they would stick to the back end there. uh freshwater people would do the sort of things that we've been doing in our course where we're constantly measuring. Um water flow, stream profiles, all the sorts of things that we've been doing in this course are standard things and that you can apply that distribution of fish or stream inverters what have you and of course marine people would be roughly where you are looking at nutrient changes in the marine estuary. And the fun thing about salmon is that they knit all three of these habitats together. So if you're going to study salmon, you could just study them in the ocean and some people do. And you could just study them in the fresh water and count fish every fall as many people do. But if your question is what is their role in the wider ecosystem, then you actually have to cover all three habitats. And not many people actually do that. As a sort of general generalist naturalist, this seems to be quite well.

[00:04:38]And so I set up a program when I uh just decided to clean up this chair as a view looking at that. And this is the kind of salmon I study. I studied as people will know but if you're with me when you're looking at fish on stream I have a pretty hard time identifying a lot of the juvenile salmon I work on much. I study I'm pretty good at identifying dead because that's the main work. So I'm interested in how these different that's together because when they are killed or when they die their hearts in the forest and just a reminder the distribution of salmon they go all the way around on the north Pacific we have most of the same species on both sides so you can go to campa peninsula for example and see spawning sai steel head and all sorts of fish that were very this side of Civic.

[00:05:37]This is a photo that you can see in uh lots of places online. And and in fact, this happens at a hatchery near my home uh in uh in Vancouver area. This uh person is wearing gloves. That's your first clue to what's going on. This is a frozen salmon that he's about to throw into the river because this has come from a hatchery. So we had a whole truckload of dead salmon and these fish were all unfortunately for them they were the the source of the next brood stock of the salmon hatchery. So people catch the fish they kill them they strip up their gamuts fix them together and bre and so what he's doing is throwing the carcass back into the river because the understanding the theory is that the carcasses cause nutrients into the rivers which can then work their way up through the food web and to support the next generation of sand.

[00:06:31]It is an interesting concept because of many of us from urban areas problems with utrofication in too much too much phosphorus in particular, right? This is this is the big problem in a lot of freshwater water bodies. But in fact in the Pacific Northwest we as long as you're away from a lot of people in fact it's the other way around. They can often be quite nutrient poor.

[00:06:57]It's the natural state is to have very low nutrients. And so it's possible that these carcasses when they rot, they'll be feeding the vertebrates which could then feed the next generation and so on.

[00:07:08]But this is another look at another side to salmon and you might even be able to hear that.

[00:07:19]This is in one of our study rivers in Bela. I'll in a moment here you have two male fighting with her position.

[00:07:30]That's probably a female up here.

[00:07:33]The males are trying to be first to spawn when she's ready to go. So, she's digging a nest and you can see it's full of salmon. They're all fighting and they're stirring up the gravel and it's actually quite striking. You can go into one of these things and you can see the areas where the fish are spawning where they're not because the rocks are green where they're not spawning and they're they've been scraped clean by their digging action. And so they've actually been studies showing that you get so many invertebrates that'll wash out of the system because of that get suspended and leave that in fact maybe there's a net nutrient loss due to the sound. They bring nutrients back with their bodies when they feed seed their weight on the seed. But then you have this effect and I remember getting corrected on this point once. I had some people at the University of Washington told me what I was studying and and immediately when I said I was studying the the fertilization effect. Immediately the person cut me off and said give me the give you mean the perturbation effect.

[00:08:32]You mean the stream engineering in his opinion it was the other way that the salmon were reducing could be reducing nutrients in streams.

[00:08:41]And I was lucky I arrived I I was previously in England uh for a number of years professor recently extended and when I decided to move to the west coast to take up this position at SIU I told some people that I was planning on doing this and people from department of fisheries and ocean said oh good timing because we've got this policy that's about to come out they had worked on it for about 10 years and the policy sets out the blueprint for what Canada is trying to do west coast center what are they for what how are they going study them, what are their conservation priorities, so on and as a result of a huge amount of input from environmental groups. They had the strategy which actually looked at ecosystem connections with salmon. So the challenge, as they said, is the need for development of an ecosystem objective that's widely appreciated but difficult to quantify.

[00:09:32]That's a fair statement. Difficult to quantify. Yes, they they get that salmon are there for more than just um fishers, fishermen, fisher women, but they're not, you know, many things eat them, but it's difficult to quantify that. And so they said few studies provide advice on the number of salmon necessary for a healthy ecosystem. And they were very smart because they didn't define what a healthy ecosystem means. You can imagine that could have delayed another five years to try to get scientists to agree what what definitions of a healthy ecos.

[00:10:02]So I was very fortunate to be allowed to work in Helic traditional territory in the great bear rainforest. You can see the great so-called great bear rainforest stretches here. It's pretty green compared to a lot of the rest of DC that's been logged uh very hard as we know around here and but this is an area that's hard to get to. There's been very little industrial blocking. There is some for sure you can certainly there is some brown areas here in waterways.

[00:10:32]There's been historical logging, but not in not large scale logging. Uh definitely in very much of the Helic territory, nor the other three nations in the central coast.

[00:10:44]So I was really fortunate. I got in touch with some people um in in band in Belladella and I was aided very much by Morgan Hawking who was my first postto there. He introduced me to some people.

[00:10:57]They took us out for a day or two uh in these boats and we looked around and and one thing led to another and I've ended up working with data from all of these sites uh all these locations. So each dot is a stream and there's my scale 20k. So the village of Elabella is here.

[00:11:18]That's the main base is about 900 to,00 people living here. And then one island over we have uh sheer water which is a it's a marina. It's a place where people stop their can stop in when they're going up further up toward Alaska. So we work in most of these streams. The color codes are just for from at that time who was responsible for counting fish. So different colors mean different things.

[00:11:45]But we have certainly done work into all of these streams. And the farthest we go for a stream town for stream work would be maybe an hour and a half by boat.

[00:11:54]That's how far we go. And um this is this is one of my one of the boats that I've been using. One of my boats research boats. Howard Ham here has led our team for about 10 years. He's from the village and he's kept us safe. He's trained successive graduate students to take over the driving and packing of the boat. And this has been extremely important. He's also, you know, our head fish counter. So when we count the fish, the person who goes first has a certain duty to certain fish in the county. He's the lead and they'll have two people at his banks. And so he directs traffic, directs our traffic. And um and we had he's moved on to a different job now, but we work very closely with from the nation and all of the data that we collect are done in collaboration with the nation. All they have copies of all of our data, all of our physical data on the streams as well as the of course the salmon data and we work with the figure who's stream. We give them the worst streams. They do the they do the really big ones where we just don't even want to go near them. We tend to this is a picture of Rosco inlet. A beautiful inland fior and u the streams that we chose really were quite variable. This was from Rosco and fairly wide by my standards kind of similar in some ways to the streams that we've been looking at in this class maybe the knitnet and uh so they can be fairly wide or they can be very narrow.

[00:13:30]Sometimes some of them are only 2 meters wide and we're primarily looking at ch salmon. That's the main dominant fish in the system. So that's larger what we're studying and we're interested in three large carnivores. This the great rainforest has arguably the tag large carnivore assemblage in the world. So even in you know we think the Arctic is remote or not or not very impacted but even compared to the Arctic here basically most of nations are not interested in hunting. They in fact many are dead set against uh commercial trophy hunting which used to happen until many of the licenses got bought up by NOS's in partnership with the nations and so basically nobody's there now in very large tracks of great nobody's shooting these things and so we have wolves which are marine uh really marine animals on the coast they are eating a lot of marine fish you can actually grab the fish, pull them right out of the stream. So, we have both bears. Uh, drizzle bears are more on the mainland sites, black bears more on the island sites. And this is a very typical thing uh that you can see at an estate. So, here's a ch salmon and see my scale. And you can see they've left behind an awful lot of um meat here. And this is to me that I'm seeing a huge sack of nutrients.

[00:15:02]So wolves can just leave hundreds, literally hundreds overnight. You come back and and some of the fish are still, you know, this clearly were killed overnight. They can actually kill hundreds of fish in the estuary and eat very little of them. And I want to play this video. This is we c fish as I mentioned. Here's how we do it.

[00:15:42]So some people are kind of dead fish. We record what happened to it. Whether it died of natural causes or was killed by a predator in the lead there. That was probably how the lead probably heard may have heard somebody yelling to warn the bears that were coming. That's kind of our standard here we come uh yelling to the bear. Last year, last fall, we got chased out of a stream twice um by a bear. It just would not let us do it.

[00:16:10]And so we there were five of us and we still said no, this isn't worth it.

[00:16:15]Backed out and it was an hour drive, hour boat drive to get there. We came back three days later and the bear was still there and it still wouldn't let us do it and we left again. So the third by then I had finished and gone back the team was able to get into the really it wasn't even a very big bear either it was a black so we have looked at many many um roots through the freshwater system from bofilm and algae look at the effects that fish are having on these also look at how they're neutrified by the stabilized by fish lots lots and lots of stream vertebrate work and we looked at effects on juvenile co I'll mention that in a moment and two species of sculp as well and then we've also done a terrestrial route here we've done some work on bears a lot of work on birds I'll mention that plants as well and we've also there's another axis I'm not bother trying to fit it in we've also done uh I imagine an axis here for the marine pathways we've done a lot of work in eststeries tracing the nutrients from everything from clams, muscles, and even as crabs.

[00:17:29]So, I'm going to give four examples of impacts that we were testing. And the first one was that fish one. Remember the the kid that was throwing the frozen carcass? Well, that story just seemed too good to be true. The idea that you can sort of jump start a stream by putting carcasses in it. And for us, in fact, it it probably could not work for most of the species because pink and chunk salmon do not with their juveniles in the river. They soon as they reserve their yolk sack in the spring, they leave. So they're not they're not hanging around hanging around. They cannot be feeding on anything that was fertilized by the generation that went before it. But coo do stay. And so here's a co. We've seen lots of those in this this course. And as you know, we've only so far I think seen one age class, which would be the ones that were born this winter, came out of gravel early this spring. They can even stay for two years and and they're really distinct size differences if they're in their second year. So we did some work on those and this is work by Michelle Nelson for HD and here you have the number of pink salmon that were spawning in each stream. And here you have the abundance of coho on a on an index. And so basically you can count these co and our class certainly saw that in decent size pools and these are really small streams you can actually quantify this and so you can see that when you have a large number of pink salmon the co tend to be more abundant in these streams it's quite variable if there are no fish sometimes they're no salmon because they don't tink or ch salmon because they're not as good jumpers as the adults as an adult coo Coho adults are the sort of most athletic of the fish.

[00:19:19]So we can get to places where they might be there will be coho salmon but there's been no impact of the nutrient and we you know to to Michelle's credit we looked at 17 habitats founded these analyses measurements and whenever no matter how we looked at it pink salmon and secondarily tum abundance were the best coralates that we have in I can't swear that there is some common stream has to be sement at all to be there, but it definitely was it certainly won the competition.

[00:19:59]And so then we moved on to birds and this took a a little bit of time. My initial idea was to count birds that we haven't used standard sens.

[00:20:15]before we did Rachel Field joined me for a masters and so she had a background in forest plots forest analyses as well as further and uh so we looked at the forest birds around eststeris so we didn't have to deal with our running water problem and so we would just anchor the boat and then Rachel did this work on quantifying the vegetation all the compound variables the birds systematic way. She also did the the ones that were feeding in. And so there's a pretty there's a not too surprising result here. So that streams that have the most biomass of carcasses also have the most birds that are feeding in there. Various species of gulls, eagles, so on. So that makes sense. And by the way, these are not all separate streams.

[00:21:11]Some of the did multiple visits to So that's all but that's not too surprising. You don't even have to get out of the boat to do this one. You just in fact she didn't. So she was scared of me just go out quietly survey the the total number of birds. So that's not a shocking one. We were pleased and interested to see though that the one thing we weren't expecting is that eagles were especially associated with fresh carcasses, not dead. Not just any old scesscent carcass which can be pretty disgusting. I don't blame them.

[00:21:43]They cook for the fresh cars and so on are happy with the other ones. But um fresh killed bare killed carcasses were the most correlated with the eagle abundance. But this is the one I really liked where we quantified the birds in the trees. And so again, it's almost all by year. And here you see the pink combined biomass. And this would be one stream. This is our biggest stream, the one with most fish. and two visits in two different years each one year second year one year another year see pairs data points if you have very few fish are not indicable results otherwise in the big ones you got both birds so first time shown that you can get a higher density breeding birds around eststeries that have more fish but the thing that was interesting to me especially is that some of These birds are migratory like pound western fly catcher. They don't feed. They're definitely not they're not even there.

[00:22:47]So they're not feeding on the carcasses.

[00:22:50]They're not feeding on flies that are feeding on the carcasses. They this these birds are probably benefiting we think just through overall enhanced insect abundance streams and with more fish and it does not have anything to do with forest structure. Rule that out based on our for structure has a huge effect on density of birds. We didn't get that study.

[00:23:16]So this is well I'll keep the story short but Kirsten Wilox was an assistant a field assistant to another PhD student studying birds that whose work I'm not going to bother mentioning right here.

[00:23:30]Um Kirstston was studying the hardest bird in the world to study which is the Pacific R. That's the one that we have around here. They're hard because they are in deep forest. Their nests are very hard to find. They nest in moss balls sometimes or under root balls and the males make dummy nests. So, you can spend all day following one of these birds. They finally have got the nest and then nothing ever happens because it was it was a courtship nest or something like that. It they can never they may end up not uh not even happening. So anyway, she did it really well and had an army of field assistants tracking these birds. And I'm going to mention how we did the screen mapping. She she colorbanded as many birds as she could.

[00:24:17]But the real question was whether we could territoriality of these birds. So here's how the territory mapping works.

[00:24:24]And this is this is her artistry year with banded birds yelling at each other.

[00:24:30]They don't really do that. Here's how it works. So these are this these are actual data here mapping data for free in this course. There you go. How's that? So um Kirsten would have walked into the stream. This is the schematic where the stream was and this is a place where she has encountered a civic red.

[00:24:50]It's probably her probably either yelling at her or yelling at another bird or singing but they have a call that's very distinctive. And she also had one here here and a here and here.

[00:25:01]And then this bird moved around. Then some distance away there was this one over here. She knows there were different birds because she could hear them at the same time. And that was basically all she got from that first visit. This is one morning of work. So then if you go back again, we're not looking abandoned birds. You go back and here's her next here's her day about three days later.

[00:25:23]Again, there's some movement, you know, moving around a bit. There's one at this end. There's one bird up at this end.

[00:25:30]And nobody And so with successive visits, you can build up the map of their territories.

[00:25:37]So pretty clearly there's two birds uh along this stream. One that had huge territories. One goes from here to here and one sort of wraps around from here up to here. And they were not they occasionally do probably each other's territories, but that's a that one was pretty discreet. And this particular place was a spot where there were no salmon at all. So there was a waterfall, no salmon. And here is how we're able to draw the two territories. There is a little no man's land, no land between in between the two territories.

[00:26:18]And then here an example from some of the other screens. She had quite a few screens. You can see the one that has really large number of fish has a lot more territories. They're much smaller.

[00:26:30]They have to pack them in.

[00:26:32]Interestingly, this there's something you can sort of see here. It held up statistically. They were they were actually more selective of where they were territories. So, some of these big gaps kind of re are actually real. They are real and they were more selective in the kinds of trees they were wrapping their territories around or the densities of trees for their territories. These are obviously right next to each other and overlapping. But in many cases, they were more selective when there were more birds. And the males are, you know, extremely busy in these here. If there's only two birds, they don't have to talk very often to remind each other that they're still there. These things is just and they are so busy uh fighting to maintain these territories. And she used a um a camera on the end of a tube to go into the nests, the ones she could reach or into the stumps. And she was able to actually look the number of young in many cases. And after they fledged, they stayed with the with the mom for a little while. And she could also therefore figure out how many were coming up per nest. And the number that were coming up per nest were about the same whether they were in the high density salmon stream or the low density stream.

[00:27:48]That means overall this classy here, this stream was producing a heck of a lot more rents than that, but the individual reproductive success was equal whichever one they were in. So they the rents were distributing themselves among the resources in a way that ended up equalizing their fitness.

[00:28:09]Okay, so plants again I hope they hope our Bfield class is entire plants. Uh, everybody know what that is?

[00:28:25]>> You know, it's a blueberry because one of them obviously that's the oval red where the red stems. I didn't see that nearly as often as the other one. But I was very interested in these. There are no plants. There are no emerging plants in the stream out. So I was interested in the plants on thearian zone. And this was when we went began this whole study of a stream called Ripley. I actually showed Ripley earlier. That's the one that has no fish in it because of this waterfall which is right near river. And so salmon can't get up this even can't manage that one. And so there's no fish at all. And so this was when my postto Morgan Hawking and I got the bright idea that we go and put fish on top of this.

[00:29:10]So, we went by boat, went to a more productive stream, grabbed these carcasses, put them in plastic bags, and walked up this bushwack up over the waterfall through the forest, and we planted them out in the middle of Grizzenberry country. And so, here's what it looks like. So, we would drop a carcass and flag it. And then we would take a sample of plants either right beside the carcass or a meter or so away from the carcass. So that was our before. We wanted to look at the nitrogen content and things like that in the plant. So this is the start of the experiment. You can see how disgusting these carcasses are we were putting out there. And then we would come back again in the fall when there would be a skeleton. Sorry, in the in the spring.

[00:29:58]Sorry, this is the fall. In the spring, come back. It's just a skeleton. We do it again.

[00:30:03]And here is one of the results of this experiment. First time anybody ever done this kind of experiment. It may be because it's so disgusting that nobody else in their right mind would want to do this. But here you see the percent nitrogen in uh three examples of plants.

[00:30:22]And so there's the percent nitrogen and here's the fall at the beginning when we did the experiment. No difference in percent nitrogen and leaves of course because there hasn't been an effect yet.

[00:30:31]We the day we put down the carcass. in the spring there's a jump uh beside the carcass much less of a jump away from the carcass there is a bit of an increase too. So you have this balance that happens in the that we can we can detect in the spring even though we put the carcass down in the fall when the plants aren't really growing very much.

[00:30:52]There's obviously some sort of effect through the soil and the plants are taking it up and having a higher percent nitrogen carcasses as a result. So that's the first time anybody's shown experimentally what a lot of people thought probably happens, but we didn't.

[00:31:07]There was no evidence of it. And the one thing I really liked was that we did this at a lot of different sites. And here you see two things here, two species, boss and stream salmon density. So these the number of fish that are naturally spawning in streams. So if you have no fish at all, then you get a fairly lines are fairly far apart. The experiment has a bigger effect like it did at that waterfall site. But then in streams that have regularly get a lot of fish, we're having less of an effect from our manipulation, which is what you'd expect because there there's already probably a nitrogen base in the soil. And so this fertilizing effect is less important.

[00:31:55]But that's percent n. So this is where I got really interested. We never wanted to stop there. The real prize I thought was to see if you could see a change in species composition. And so this is where the great quadrat fest happened.

[00:32:11]And uh and again I'm sorry this but we put down the put down these quadrats perpendicular to the screen.

[00:32:22]Did a lot of these we went 50 separate streams didn't work. There's Morgan Hawking who led this stud. post and here's the transact tape that we looked at the diameter breast pipe of over I think it was 6,000 trees we have over 30,000 lines of data from our quadrats we generate a lot of data this way if you go to 50 different waterheds and so we were able to predict which ones would respond uh which ones would be more common in streams that have more salmon because they already known from other sources. We knew that some of these things like false study of the valley, salmon berry and stink current were all in typical of nutrient-rich soils and in fact I think these three were very dominant in the two and the three again very rich flood planes there and then Salan fall they can grow just about anywhere they're not dependent on that kind of external source of nitrogen So we predicted there'd be a shift in composition from as the number of salmon increased across rivers toward the nitrogen rich ones. But we also looked at the N15 which is the nitrogen isotope that is amplified when it's coming through a marine source such as salmon especially a high level source. And so here are examples from two nutrient poor indicators. So these are two species where in fact they are taking up salmon drive in. So that's what we're seeing here. Each dawn is a different stream.

[00:34:07]So we had 50 streams and you can see from 0 to 30 um kilograms per meter squared of fish. They're taking it up.

[00:34:16]So the these these nitrogen pour indicators are taking it up. uh and then so is everybody falls slowly there's salmonary very similar striking similar curves kind of a surprise but then if you look at the percent nitrogen so do they have more nitrogen they may have more of the isotope but is it just taking out the other isotope and the answer is there's no pattern whatsoever for the nutrient poor indicators these are not they may be taking it up but it's not increasing the nitrogen in the leaves whereas these two it is increasing it and salmon uh at least the highest densities show reasonable response. And then if you look at the densities, here's this community shift that I was predicting we would find. So we have a a drop in the these they're called hericacious members of the family like aelia and blueberry. They're dropping no effect on false lily and the salmon berry are increasing. lots of scatter and I'm going to talk about that in a minute, but salmonberry densities are higher. We've subsequently done a study where we actually found that salmon berries have more berries per plant when there's more salmon in streams and uh but the sugar content does not differ. And so we because they're in the same genus as raspberries, we were able to there was tests available for how to look at the sugar content, how to process them. You squeeze squeeze the We went through the whole rigarola and found no difference in sugar content, but we did find a difference in the berry berries per plant. And so here's a way to put this all together. Here's if we array all of the plants on an axis that describes their affinities for being a nutrient-rich indicator, then you go from a very nutrient-rich community to very nutrient rich poor community. It's not just these two plants. It's putting it all together and then relating that to the density of the stream. And you can see that again lots of scatter at the low. So there's other things controlling these things at the low numbers and then it starts to rise pretty nicely at the top. The when we're doing this, it's a correlative study. So the first so of course we're thinking well okay you know it's not experimental. I showed you an experiment and I will never forget actually when uh Morgan came to my office and he had just done an analysis because we were there to just see if we could understand the variation above and below above the line and it turned out that two key things seemed to explain how most of that variation or a lot of it one and they're both to do with other things in the streams. One was that these really steep gradient streams don't tend to benefit from salmon nutrients very much. So the nutrients are not going to be retained on a bank like this. And we found that these sorts of streams had really very little effect. Didn't matter if they had a lot of salmon or a few. If it was like one of these canyon type streams, we saw no real effect on the really steep banks.

[00:37:33]And then the other one, thank goodness we thought of this beforehand, was that the of red alder was important because that's a nitrogen fixer. This will actually produces its own nitrogen makes it available bioavailable in the soil.

[00:37:45]And so we had measured red alder in case that was the case. And sure enough, if you have a lot of red alien rich indicator species because they're all they're already there because they've already got a different source of sand.

[00:38:07]So it was the first I mean I don't want to overstate this story. Um I think if you took you know a salmon stream I could probably tell you if they have very few or middle amount or large amount. That's about as far as I would go. I think I can I think I could at least in that in that region I think I could do it but I you know we have to I don't want you to think as some people do that if the sand disappear you know the whole thing's going to collapse and everything's going to change and it's a small effect and it probably so there's a lot of wear and tear on the researchers when you're multiple sites per day different day, a different site all the time. And I had this fantasy really nice if you just stay in one place and do something in one place only. And my the thing I really had always wanted to do was to work in salt marshes because they're just beautiful. Uh lots of plants and if we could be in one place uh we could get a lot more done and uh save some fuel and everything else. And along came Alison Bennett for her PhD with me and let's fly over goat blue salt marsh here. This is her study area.

[00:39:24]See the dots you see these are rays here. I'll tell you about those in a minute. This is gosh. It's about half hour from uh where we are. So you you anchor the boat out here and then you pike up and then you get to these places where we have these patterns. And this is because we designed an experiment where we did four different treatments, you know, a block like that. So there was a trail leading from one block to the next.

[00:39:54]That's what that trail was. And then there were blocks, those dots were the blocks where the actual experiments were going. This was one of the riskiest things ever. We had a plan B in case it didn't work because we didn't know first of all for sure that if we put out carcasses in these blocks that they would stay there partly because it's a salt mar so you can get a really high tide. So we st them down and hoped the bears would uh and it was also risky because because of this flooding thing it could be that that would swamp the rocks and therefore the any carcassy might have no effect.

[00:40:31]So we did have We had a plan B and a plan C, but we just had to try it. And so here's Alison. You see there's a painting here, us rotten fish. So, uh, this was an all hands on deck. She got everybody going brought these carpasses here because they weren't very many didn't want to ride background. And then she had 25 plots, a meter by meter plot.

[00:41:00]um each each square was a meter and so there were four of these one meter squares things and so we had a control where she did nothing added a salmon added fucus rockwheat or added both salmon and rockwheat so these are the that's the plot that's the treatment 25 um replicates of this thing and she did it for three years and uh and I I brought in a co- supervisor who's who a talk about the pollinators and identify bees and whatnot because we wanted to see if it affected the the plants but also it affected the pollinators of the plants.

[00:41:39]So we chose four focal species for most of the work and these were all in full bloom in in September October when the work was being done. So we focused on these four things in her plots and then um Alison and an assistant would count all the visitors that came to the flowers. It was mostly flies and bumblebees. And so literally you would stand there on a sunny day usually because that's record all the visits that were happening and first in one pot.

[00:42:14]So and so it gets although it's a beautifully elegant design that came up with. It gets a little tricky to disentangle what is affecting what. I'm going to make a long story very short and this this work has been published. The most of the plants had larger flowers in plots that received salmon whether the salmon was with pupus or not. Bigger flowers for for the most part. They many of them some of them had higher seed set as well later on. And then as far as the floral This is just one path that was shown. So here yrow had 65% more stems in the plot where she dropped the carcass and 6% more visits floral visits by insects.

[00:43:05]So that one that treatment had this pathway of what we believe is causation.

[00:43:14]I think it has to be because it was an experiment whether we control or what we get down. And so each of these treatments has arrows. This has many arrows in the whole thing. Could be a graph full of arrows, but it has been we have published it. If you want details, you can get there. But it's the first time someone has shown that salmon can have a ecosystem effect that can go up not only through plants, very few experimental studies of plants, but then also have this secondary effect on business. So I wanted want to just come back to the context of my study here. I have not shown you a lot of the things we've done. I can assert some of the things here about check mark being yes effects were as predicted for sculpins and things like that. And uh I talked about the birds. We've done a lot of a little work on grizzly bears with vitality their PhD cos supervised by me and so I want to go back to how I one of the things that coincidentally was inspiring me I I thought this was just going to be a fun ecology study and then same as I was trying to put it together the department of fisheries and oceans had come up with this goal of trying to devel an ecosystem objective. We have done a lot of work on this in which we've now summarized studies by other people and so I'm not going to show you the graph but we wrote a big review of this where we found a very large number of published graphs ours and other people's looking at different aspects of this. We redid all the analyses from all of the graphs. led by Jessica Walsh who's now professor at University of Queensland and we looked at how many times basically what is well that we're trying to answer this question where is it how many sand do you need and so what we asked was what does it look like how often do you get an asmtote like we do answer is not very often most studies don't go don't have enough fish I think to have found that as the people working on bears Alaska have certainly found them and it turns out that there's no magic number for a while. I thought I thought we had a magic number just based on our own work. I can say fish per meter squared or that sort of thing. But no, as you can imagine that simply it depends on it depends on what you care about. If you care about birds, it's one number. You care about co salmon growth rate density it's another number and so on. But we've got those numbers. Those numbers are now in the literature and they're now summarized.

[00:45:54]In the meantime, that poor old wild salmon policy never got implemented. So, people just decided it was uh that it was nobody's job to implement it. And in fact, there was a federal judicial inquiry into the loss of of salmon and South by salmon from the Fraser River where that the commissioner Cohen repeatedly chastise the Department of Fisheries and oceans for not implementing their own policy.

[00:46:21]He pointed out nobody was responsible.

[00:46:23]It was nobody's job to grant it. And so it kind of languished. We wrote, we attacked this from many directions.

[00:46:31]Jessica Walsh. She's the lead author of this. She's the one to speak with you.

[00:46:36]We've we've tried many ways. I've talked to various um people about this. I' I've various ministers of fisheries and so on. And the bottom line is that people do appreciate that salmon are important for what they're interest.

[00:46:53]But things have shifted. The number of salmon in that are coming back in southern rivers has declined. It's become less.

[00:47:04]I guess it would be a luxury to be reducing fisheries in order to help bears or eagles. At this point, a lot of it's all hands on deck for a lot of southern salmon streams, Fraser in particular, uh, and a lot of populations, some of which are endangered. They're actually danger.

[00:47:23]So, the ground has shifted in the 20 years since that policy came out and finding enough for healthy ecosystems would be great, but right now a lot of people are just trying to find enough salmon to have the next generation of salmon survive and and fisheries unfortunately for the people that depend on are very often not open have the openings that we used to fisheries but there are still some great runs there still very healthy populations and definitely I think what I learned is that ecosystem study subsidies can translate into management decisions but We do have to decide what the targets and tradeoffs are, how much we think about.

[00:48:05]So I'll leave it there with a shout out to an army of students and posttos uh who have supported this work over the years. That's and that's only from the first three years. So it's it's gone on ever since and is continuing partnership.

[00:48:24]So I'll leave you there.

[00:48:35]update.

[00:48:41]>> Okay. Anyway, I'm happy to answer any questions.

[00:48:52]>> Okay. All right. I think we know I think we know who you're voting for.

[00:48:59]Um yeah, anything any other questions?

[00:49:04]>> Yes.

[00:49:05]>> Um do we know if the insect like um uh population or sorry if the community changed as well or did they just look at like the number of visits?

[00:49:17]>> We just looked at the number of visits within you know an experimental array so we didn't have like a streamwide >> comparison. So, uh, that we don't know.

[00:49:27]But I'll tell you something we do know that I haven't mentioned. Um, we did a study of parasettoid wasps. I never thought my ecological journey would lead you here. Paras wasps that parasitize the magnets of the flies that eat carcasses, right? So, if you see often you'll see a carcass with magnets. Well, there's a parasitic wasp. So, these wasps are more common.

[00:49:52]We They're more common on streams that have more fish. It's not too surprising because they're they're eating these sort of maggots. But we also did the M15, the stable isotope trophic signature. And so they are above uh killer wells and because if you think about it, southern resident killer wells eat sand just like flies eat sand. So that's they're equal at that rate, but they're one above that because they eat flies that eat sand. So it's If killer whale had a predator, it's its isotopic signature would be the same as parasite. So we still haven't found a way to capture that excitement, but >> very cool. Paris was very cool. So >> why wolves are not the whole salmon?

[00:50:49]Like I've never seen that. Just the head chopped off. That's not always like it's not always but they go for the head but I don't know I don't have any background in the same >> they usually they usually only go for the head they do that crunching up the head and of and sometimes it's just the brain uh that they're eating and the the theory is that there may be a parasite in the musculature selected to avoid there may be something parasitic and but I've never able to track that Don't know if that's true or not, but that's why we can tell who killed them.

[00:51:26]Most of the time you tell who killed the fish because it's a bear. They will take the musculature. They won't eat all of it, but they're quite a different foraging pattern.

[00:51:38]>> Yeah, I should find that out because I get asked this every time I show that photo and I've just gotten so used to the fact, but I've never figured it out.

[00:51:52]My other question is when you were surveying the birds near the waterfall, how did you overcome the noise of the waterfall?

[00:52:01]>> Yeah. So, so at first we avoided even doing stream work with birds because that problem. Um, we don't work right beside a waterfall. Five of our streams have a waterfall and so we avoided being near the waterfall. But after a while, I sort of realized that, you know, these these rainforests are just gripping with moss and they're kind of like a soundproof room, they really actually you notice when you're talking to somebody in the forest, how different it was. And so if we just stepped, we didn't point count. So we had randomized selection to go find that random location. And so we didn't have them right beside the stream. Sometimes it would be survive, but usually they weren't right on the street. So there's a whole another study that I haven't actually talked about where we actually looked at density for right in the forest. We had similar results but we didn't have to the only thing was hard there was getting it was like for a geocache GPS and and when we chose them randomly there was no consideration a tree that's So for the body where there's more like isn't the really close by so they affect each other.

[00:53:35]>> That's a great question. We there could be some spillover but First of all, let me talk about insects.

[00:53:43]It could be that the insects are drawn to the one with the biggest most flowers and then while they're there, they go next door. So that you could imagine that effect could occur. To avoid the nutrient thing, we did it the best we could. We used a machete and cut the soil between the pots. So, so at least there were not roots transferring nutrients across. That doesn't mean that the soil could be.

[00:54:10]So, so cutting them cutting them was the best we could do and it was turned out it was good enough to get significant results even though probably wasn't perfect.

[00:54:25]Is it better to do it like the whole thing is just like one >> if you put in one and then like >> Yeah, that would be the other way to do it. We could have um Yeah, >> but and I probably would have wished we' done that if we hadn't gotten a significant effect.

[00:54:55]But but we got away with it. It's pretty nice for practical reasons and all sorts of others. It's pretty pretty nice if you can have this randomized block design.

[00:55:07]It's kind of a classical thing in ecology. I think the spilling over portion was too much.

[00:55:15]>> Yes, that could have been another way to do it. I guess the other thing with these that these salt marshes are more complicated topographically that looks like from the air from the photo. So you could take I could take three steps here and I might be this much lower right and or there could be well avoid it but there could be creek running through it.

[00:55:37]So you know it'd be very easy for there to be localized differences that could make it messier to interpret the results. So having close together. That was one of the >> Yes. Because you know a meter by a meter. So you're only going from here to here basically our square a little bit more than that. That was a lot better because it is pretty rough walking. Believe it or not, you could be you could be heading to if you're not on the trail, you're heading to the pod and the next night somebody disappears. Literally they're where did they go? And it's because they stick down into a hole and it's tall grass, tall and so it is a little it's complex.

[00:56:23]>> Thank you.

[00:56:24]>> Yes.

[00:56:40]>> I don't think we got much of an effect.

[00:56:42]um we did not publish in that we published almost everything we had in one paper and and it wasn't in there and I don't remember what we ended up doing but I think we didn't get very much effect other people in particular Tom Ry have done work on growth rates of trees by looking at tree rings it's really technically difficult it took him a long time to crack the problem and and we used to talk about what he was doing and some of the challenges of interpreting the stable isotopes in the tree rings.

[00:57:15]There were many other things going on.

[00:57:17]So I never touched that. He was working on it and that was his thing. But he certainly has shown faster growth rates at least a couple of species of trees that he's nearer to salmon basically. He he is picking up he has picked up some effect and he he's published a couple really nice papers and his team on that.

[00:57:43]college professor.

[00:57:45]>> Yes. Yeah. He so and in fact he used to work in Bella >> and Morgan Hawking my postto was his PhD student. So, so he he I'm kind of standing on the shoulders of a giant >> there and he he was no longer working in the territory, but I a couple of my sites he mostly studied three watersheds and study all three of those plus a lot.

[00:58:19]One more round OF APPLAUSE.

[00:58:26]SO MUCH. That was fascinating and awesome. Thank you so much for sharing your fun and knowledge and thank you all so much for joining us this evening.

[00:58:33]This happens every Tuesday from now till the end of the summer. If any of y'all are sticking around for another course, maybe maybe not, I don't know. Um there's between tomorrow, deep sea on Thursday back and other please enjoy the rest of your evening. Any announcements?

[00:58:51]I think they know you know what you're doing.

[00:58:56]>> Yes. No, I think we're good. And uh yeah, and yeah, I appreciate your support >> coming out for the story. I'll leave that there.

[00:59:05]>> Thank you so much.

[00:59:06]>> All right. Thanks,