Lake Maurepas Monitoring Project - Spring 2026 Update

Hinzugefügt: 2026-05-10

[00:00:09]Overlooked as a major landmark, Lake Morapal remains relatively obscure to many except residents of adjacent parishes and those traveling the I-55 corridor.

[00:00:21]Recently, however, this smaller body of water has risen in profile due to two developments consequential to the environmental health of this highly fragile ecosystem.

[00:00:33]One would be efforts to utilize the geologic structure underneath the lake to store liqufied carbon-based industrial byproduct via a process known as carbon sequestration.

[00:00:47]Cited as a curb against harmful atmospheric emissions, this complex procedure will be part of a new blue carbon manufacturing facility in Ascension Parish, owned and operated by Air Products, an international corporation that maintains other carbon capture arrangements throughout the globe.

[00:01:05]Also involving Lake Mara is an ongoing scientific campaign to carefully monitor and document environmental conditions within the lake in anticipation of these planned activities.

[00:01:19]Begun in 2023, the Lake Morapal Monitoring Project was established by Southeastern Louisiana University to provide a database of crucial information related to indicators such as water quality and aquatic biodiversity as well as other important markers of environmental sustainability.

[00:01:41]Researchers at Southeastern are entering their third year of obtaining and interpreting this data. All as part of an innovative project undertaken by the university in service of both scientific discovery and civic responsibility.

[00:01:57]So when you have boots on the ground, you've got researchers in the field and when you look at what's taking place at Lake Mara and in the research, it it provides a much broader perspective of the work that's being done, not just within the lake itself, but all the rivers and tributaries that feed into Lake Marupal. All of those touch communities, they touch areas of growth.

[00:02:18]And so having our finger on the pulse of the health of the lake and and what's what's being accomplished there is is vital. We can educate our our thought leaders. We can educate uh legislators uh in those impacts and and that's important so we can begin making informed decisions about the future.

[00:02:40]For scientists at Southeastern Louisiana University, the Lake Morapah monitoring project represents an expansion of existing efforts to study and conserve a unique natural resource. The logistical command center of these initiatives has been the Turtle Cove Boatshed Complex on the Galva Canal in the lakeside village of Manshack, Louisiana. This facility is a focal point of all field research in and around the lake and also provides staff and visitor access to the Turtle Cove environmental research station located in Pass Manshack. Turtle Cove serves as both a headquarters for all field research in and around the lake as well as a valuable educational tool informing visitors about the nature and value of this unique natural resource.

[00:03:29]They're interested in how to find out more, where to go to look at our data that we collect, where to find reports, just so they know what's publicly available to them and they're surprised to know how heavily we're involved in collecting environmental data and surprised to know that they can keep track of it at home and see what we're doing. We get a lot of questions from the public first of all because all of our information that our scientists are getting immediately goes to our website and every year we have a big annual report that summarizes all of the data that has been collected. And of course with the water quality monitoring buoys that we have out in the lake, those are real time and that data is downloaded every five minutes or so to our southeastern website for the lake Marupal monitoring program and so people can see the local community can see what the water quality aspects are. Another thing that's increased is the need for more boat slips. This is our uh southeastern Turtle Cove boat shed here, but right behind us is another boat shed uh that we share with wildlife and fisheries. So, we had to get three more slips over there to accommodate all of the use. Vehicles to pull the boat trailers with the boats on them if we're going to different places or for maintenance. Um so lots and lots of impacts of all of our infrastructure and facilities and staff and boats and all the training also that goes along with that. So all of those activities have increased greatly because this is the access point.

[00:05:14]A small fleet of research vessels at Turtle Cove is kept busy in part by a need to maintain and expand the infrastructure required by such a comprehensive scientific project.

[00:05:26]This practical work of creating and deploying needed structures and instruments is of main concern to those tasked with observing the most basic yet perhaps the most important component of the Lake Moropa ecosystem, the trees and other plants living in and around the lake as well as the sediments that sustain them.

[00:05:48]Our work is very labor intensive in terms of installing our sites. So, we've spent the last year installing 24 survey plots uh in the marshes around Lake Moripal. Um and uh so that's what we've been doing over the last uh year, installing those survey plots uh getting baseline data on all the trees within our survey plots. That's over 1,200 trees that have been tagged and monitored over the last year. uh those trees are going to be monitored annually, you know, for the foreseeable future. Within those sites, those 24 sites, there are about six sites that have sediment elevation tables. We've had to build um new boardwalks around those sediment elevation tables, making sure not to disturb the sediment, and that way we can start to collect elevation data. Um and we've also collected soil cores at each of those sites. Those soil cores are going to help us um describe the soil types in these areas.

[00:06:52]Since we have these sites established now, we're in the middle of collecting seasonal vegetation data and annual tree growth data. So being able to track trees annually, their growth, their diameter growth uh over time, that tells you something about the health of trees.

[00:07:09]So we have the baseline data now. Next winter we'll do our first year data collection and then we can calculate a growth rate.

[00:07:18]We did do a remote sensing analysis of the wetlands around Lake Ponchet Train.

[00:07:24]And so that analysis which uh looks at satellite data and the vegetation around Lake Ponchet Train um showed us that there are five different habitat types around Lake Ponchet Train and the most dominant habitat types are closed canopy and an open open canopy swamp. Um and that is very much in line with the description of this area as one of the last and largest big freshwater coastal swamp areas. Uh so that is something that early analysis has shown us. So in this area we have closed canopy swamp, open canopy swamp, marsh, fragmented marsh and what we call scrub shrub area.

[00:08:06]So we have been able to characterize the wetlands around Lake Moropa into those habitat types. We do have our sites installed in each one of those five different habitat types and are a are starting to collect baseline data on the tree communities and other vegetation communities and the soils in those areas.

[00:08:27]Next winter we'll do our first year data collection and then we can calculate a growth rate. um certain areas have a higher growth rate, other areas are going to have a lower growth rate and so you can uh get a sense of the health of an area from that. In the same vein, we also look at seasonal changes in the herbaceous vegetation which are more like your grasses and flowers and herbs.

[00:08:52]Um we look at what we call total cover um and also cover by species. how much of an of this particular area is covered with vegetation versus not covered with vegetation and what's the species diversity. All of those parameters, cover and species diversity, the species that make up that diversity, are they invasive? Are they native? All of that together can tell you something about the health of an area.

[00:09:22]Within the first few years of the monitoring project, research in and around the waters of Lake Morapah has been constant, intense, and in many cases quite revealing.

[00:09:34]So, in the last 2 and 1/2 years or so, we've collected about 140,000 individual fishes um representing more than 50 species um across Lake Morip. So, for example, we collect lots of young in the air or juvenile catfishes. Um, which is a positive sign because we know that Lake Morapot is a lake um that's rich in commercial catfish fishing. So, we get large numbers of catfish, which is positive. Um, other members of my team are focusing on uh assessing invertebrate populations, particularly blue crabs um and rangia clams and brown and white shrimp.

[00:10:17]We know how the blue crab populations uh move around the lake. There are certain times of the year where they're more abundant in certain areas of the lake.

[00:10:24]So, there are seasonal changes in densities and abundance throughout the lake, which is um an important uh aspect that I'm sure the commercial crabbers already know where they are at certain times of the year, but we have data that supports. They do move around a lot.

[00:10:38]What we find is that we predominantly get male blue crabs in Lake Morip, which is an agreement with the known life history of that species, the males move into the upper ends of estuaries. Um, it's literally 9 to one males to females that we collect in in Lake Moral. Um, we primarily get uh rangia clams. These are the clamshells that comprise the the gravel roads of Louisiana historically.

[00:11:05]Um, we get they're very abundant in Lake Pont Train. Um, but we pretty much only get them in the area on the western end of past Manch where the salinity is a little bit higher. We found that we pretty much get them there and really nowhere else um in the basin. The other component is that we are focusing on brown and white shrimp. These are the commercially harvested and managed shrimp in the state of Louisiana. Lake Morapah was proposed as a shrimp sanctuary um 25 years ago. Um and unfortunately we've only collected about seven brown shrimp and two white shrimp.

[00:11:41]So white the the shrimp populations there really don't exist there. We don't have a lot of historical data to assess whether this is a recent change or the whether it's always been this way. We simply don't know. Um we use the same sampling gears that the state of Louisiana uses along coastal Louisiana.

[00:11:58]um we get large numbers of river shrimp.

[00:12:01]These are different species. So we know the gears are working. They are effective but we simply don't get the commercially managed species. The other aspect is my under my graduate students are working on environmental DNA monitoring. This is simply we go out collect a water sample use genetic techniques to amplify the fish DNA that's present in the water. We've collected about or identified about 64 different fish species based on environmental DNA alone.

[00:12:28]Gulf sturgeon are an anadimous species.

[00:12:31]That means they live in the ocean and they come into fresh water to reproduce.

[00:12:36]There are populations that are known to go into the rivers in Lake Pont Train, but they were previously not known to occur in Lake Morapawa. Last April, we collected two uh gulf sturgeon in Lake Moropa, which suggests that they're either simply coming into the lake or potentially moving into the rivers in Lake Morapal for reproduction. We also detected a young of the year or a juvenile Atlantic tarpon, which was previously also unknown from Lake Moripaw. Um that was collected up near the mouth of the Tikpaw River um last spring as well. So those are two new additions to the to the species fish species community in Lake Mora that we didn't know were there. So the greatest diversity and the greatest abundances of fishes in Lake Morap tend to be in the area in the northeast portion of the lake near past Manshack and that's likely due to the slight elevation of salinity that comes in from that from the uh past manhack. Now, we know that in Lake Ponet Train and in like Lake Morap since the closure of Mr. Go, um the salinity has steadily dropped. So, it's more fresh than it historically was. Despite that, we still get red fish. We get white trout. We don't really get speckled trout there.

[00:13:55]We get white trout there. Um in Lake Moraba, more so in the northeastern portion of the basin. We also get largemouth bass. Um unfortunately um we did a quick sort of estimate of catch numbers, catch per unit effort, how abundant they are. Um and the catch per unit effort of largemouth bass in Lake Morapal tends to be slightly lower than you see in other southeastern lakes. This is sort of the typical fish community that we would expect to see there things that are slightly tolerant of slightly elevated salinities and those that are tolerant of pure fresh water.

[00:14:40]Pillar's detailed census of common aquatic species is complemented by intense physiological analysis conducted by a team led by Dr. Chris Murray.

[00:14:52]Thus far from our sampling for a little over two years now. Um, if we just maybe think about alligators for example, we we notice that there's a very uh very sustainable alligator population in Lake Moraboth. Um, there's a ton of habitat and from the physiological perspective, we really don't see any stress that would be outside of the normal variation.

[00:15:20]You think about frogs, we sort of see the same thing. Um, there's a lot of frogs, right? There are really popular recreational harvest around here as a natural resource and we don't really see any physiological perturbations in frogs either. The interesting stuff comes when we think about what's under the water.

[00:15:40]Right?

[00:15:42]So catfish overall I say are are becoming more and more interesting to us. uh here in Lake Morpa we see some sort of localized patches of indications of stress but what we actually don't see in those localized patches of stress is any indicator of the presence of some sort of toxin.

[00:16:06]Right? So our livers look really good where we seemingly have high stress and our livers actually don't look as good in places where they're not sort of uh portraying any evidence of physiological stress response. So we use one marker lucasite profiles to think about is the animal perceiving a stressor both externally or internally. And where we see sort of a little bit higher stress, we actually don't see indications of some environmental toxin being processed that's putting stress on internal organs. We actually see a little bit of liver fibrosis, some um hpatic vacuulation, right? The livers look a little weird um in spots where we don't actually see perceived stressors. So there could be two things happening in catfish, right? where maybe we've got the maybe we have some amount of environmental toxin present whether that be heavy metals or other types of contaminants um that's sort of becoming a physiological challenge for these catfish. Uh and then in other parts of the lake we maybe see that there's some sort of um thing in the environment that's making them feel a little bit stressed out that maybe is probably not internal but rather an external stimulus.

[00:17:29]Crabs are the interesting one. Uh so we we definitely are finding some potential evidence of contamination that seems to be bioaccumulating in our crabs that's resulting in changes in gill morphology.

[00:17:44]Uh the gill is a uh pretty much global indicator of of um of how much contaminants are uh being sequestered in these organisms and how they're affecting the organisms's physiological health and well-being.

[00:18:03]I mean, crab gills are pretty sensitive, right? anything that has to filter that much of the environment through its body constantly. All right. Um you're going to see you're going to see pretty easy indication of negative impacts that um that may be affecting the ecosystem. And for right now, all we're really seeing is indications of contaminants in crab gills and some hpatopancreas in both crabs and catfish. Um one of the interesting parts is that we've seen this before. Actually, a lot of the published literature that we're comparing our crab morphology to is out of Africa. Uh it's actually the very similar species of crab. Um and our our images that we're finding from our hisystologology, right, our study of the tissues here, um look identical to a lot of the morphology that uh that we're seeing in Africa. We don't actually have very good Southeast US comparisons of crab morphology, at least that's readily available.

[00:19:04]But we're seeing all sort of the telltale signs of potential heavy metal contamination that we've seen numerous times in other parts of the world.

[00:19:16]So, I'm I'm really not alarmed by any means about what we're seeing in our catfish just yet. Um, we've still got another 120 to to paw through this year.

[00:19:27]Um, the crabs are an interesting story.

[00:19:29]We we we have to we have to take a much harder look in terms of sending off a lot more samples for for analysis um to really get an idea of how prevalent are these what I would call pathologic morphologies in our crabs this year.

[00:19:52]So our job as scientists is to build a case. So, we try to have evidence that supports a hypothesis, a theory. And what we've noticed is Dr. Murray's results have shown that when they look at the the the wildlife, look at the crabs and the alligators, and they're looking at the tissue, the tissue is showing that that gil necrosis and the the damage that we would associate with heavy metals.

[00:20:17]Initial steps taken by the monitoring project team to determine the presence of chemicals in Lake Morapah involved the analysis of numerous water and sediment samples obtained via field research.

[00:20:29]These samples were found to contain high amounts of two chemicals in particular, nitrogen and phosphorus.

[00:20:37]The nitrogen and phosphorus tend to be associated with agricultural products.

[00:20:41]is with very often fertilizer, but it's hard to say exactly where it's coming from. The ammonia nitrogen was at normal levels. However, the total nitrogen level was particularly high. It was several times higher than the recommended EPA limit and the total phosphorus was kind of at the maximum level that the EPA recommends. similar the chemical oxygen demand the average number it peaked higher than it should but the average numbers were about at the maximum recommended level. Uh additionally the heavy metals so these are things like lead, arsenic, mercury, we know that these are damaging to humans. We know that these are damaging to wildlife and looking at those the arsenic levels were very high. The lead levels were also high. The mercury levels were not particularly high in the water, but were found to be high in the mud and in in the sediment at the bottom of the lake bed, as well as some of the plants. So, these are things that now we need to investigate.

[00:21:44]One thing that's really important when you're doing analytical chemistry is to establish where sources of pollution are coming from. to establish not just what areas are associated with what pollutants but to look at things over time and to see if there is a genuine linkage between things. This is where Dr. Amaby's research turned out to be particularly valuable.

[00:22:22]The statistical analysis that resulted from this showed that there were six general sources of contamination within the lake. There were three sources associated with river inputs. There was um a source associated with the death and decay of biological species. There was geological release of contaminants.

[00:22:51]And there was a final uh catchall category which combines the effects of transportation, recreation and accidental release. River input one which was found to correlate with amat was found to contribute substantially to arsenic levels that were found within bar.

[00:23:16]uh river input two was found to contribute copper and barerium two elements of lesser concern.

[00:23:28]Finally, um, river input three, which was found to correlate with tickfaw during the summer months and the blind and amate rivers during the fall months, was found to contribute more generally to all metals that were observed within the lake.

[00:23:51]Currently, additional data related to water quality is being obtained by buoys placed near the mouths of the rivers feeding Lake Morapah.

[00:24:00]Members of the monitoring team are also collecting samples farther upstream, testing for many of the same suites of chemicals referenced in previous surveys of water samples taken from the lake.

[00:24:14]In terms of transportation, recreation, and accidental release, the three things that was found to contribute to were mercury levels, chemical oxygen demand levels, and cadmium levels. Now, we know that there was the super fog pileup accident at Pass Manshack on October 23rd of 2023.

[00:24:44]And it's likely that that was a substantial source of cadmium contamination within the lake because things like um the um wire beads and tires, brake dust are known to contribute to cadmium. Um we also know that during 2023 there were dredging operations that were going on in the Blind River. It's likely that that also contributed substantially to the transportation, recreation, and accidental release associated contamination in Lake Marupa.

[00:25:27]So, our next step is really to now analyze the tissue samples for chemicals. If we can find that the catfish and the crabs actually have heavy metals in them, that's now a pretty strong link. Uh so what we have done we're trying to we have the samples collected. We need to complete all of the heavy metal analysis. So far they've begun doing the mercury analysis and found that the mercury analysis in the catfish is very high and in the crabs is very high. Uh it's two times the recommended amount of mercury that you shouldn't eat in one meal in one fish.

[00:26:02]So that's alarming. And in fact Lake Marupon now has a mercury advisory for the lake. So we would expect that this is probably related. So we have some strong data so far, but we need to continue taking our weekly samples, continue to do those chemical analysis.

[00:26:20]So we need to complete the analysis on the samples that have been collected that aren't yet analyzed. We also need to continue taking more samples. Again, that pattern the over time and over space, we need to really have a full picture of that pattern. So we're going to continue do doing that.

[00:26:50]One thing we found out at the beginning of this project is that there had been no scientific studies of Lake Morpa forever. I mean, it was uh kind of our joke was it's the forgotten stepchild of the Louisiana wetlands here. And so when you try to make claims about the health of an ecosystem and there's no science to back it up, you really can't do anything of substance. So our work has been critically important. We now have real scientifically based facts which can then explain to us what's going on.

[00:27:18]We know a lot more about the wetlands and we know about the stresses on the environment. So we now this lake Morpa has gone from being one of the worst understood or poorest understood ecosystems to probably the best. So now when people are worried about the lake, we have some science to back it up, which is I think critically important.

[00:27:35]>> We're actually sitting between like more >> our education and public outreach program has increased significantly since we've been involved in this project.

[00:27:47]There are a lot of school groups around the area that have, you know, started projects on environmental aspects of the lake based on the information, the data that our buoys are collecting. That's just one example.

[00:28:07]So, I think that this is going to be sort of the blueprint for how projects are done in the future where you do have active environmental monitoring at the beginning and then throughout. So, um, the more knowledge you have about your ecosystem, the better things are going to be.