Balanced hydrilla management key on Harris Chain

Too much of a good thing is a bad thing.

Cliched as it may be, that phrase bears resonating application to the Harris Chain of Lakes — in more ways than one. Specifically, we’re referring to the hydrilla growing in various levels throughout the fishery.

Some view too much of this “grass” negatively, while others look at excessive grass management with equal disdain.

According to the Florida Fish and Wildlife Conservation Commission (FWC), this invasive plant (Hydrilla verticillata) native to Africa and Southeast Asia was introduced into Florida (likely through aquarium dumping) in the early 1950s and by the early 1990s occupied more than 140,000 acres of public lakes and rivers.

Unlike northern waters, where harsh winter seasons help moderate aquatic vegetation growth, southern fisheries — Florida, in particular — see far less cold impact. Winter reductions occur, but hydrilla returns quickly. 

Defining tenacity, this plant has historically proven extremely difficult to consistently manage because, once established, it produces millions of reproductive tubers per acre.

OPPOSING VIEWS

Consistently, there’s not a lot of middle ground with hydrilla — folks love it or hate it.

One’s perspective depends on how they enjoy the waterways. For anglers, it’s simple: Grass equals bass. Like all aquatic vegetation, hydrilla filters water and promotes lake clarity, while harboring the forage that feeds bass and other sport fish. Hydrilla’s an easily targeted habitat that welcomes a wide range of presentations.

On the other hand, pleasure boaters, water skiers, and swimmers find topped-out hydrilla limiting and generally prefer complete eradication. Moreover, FWC’s hydrilla summary notes that the plant’s density can cause water flow (flooding) issues in canals and rivers, create mosquito breeding areas, shade out native submersed vegetation and increase bottom sediments.

At this point, where worlds collide, B.A.S.S. Conservation Director Gene Gilliland wants to steer the conversation away from an all-or-nothing demand.

“When you have lakes where people are skiing and swimming and boating, along with all of these other stakeholders, we want to make sure (anglers’) interests are taken into account,” Gilliland said.

Multiple user groups, often with competing priorities, will forever be a Harris Chain reality. To this point, Gilliland said B.A.S.S. respects all lawful uses of public waterways but expects anglers’ rights to carry equal weight.

Fishing has long fueled an economic engine that helps support local economies, while fishing license fees contribute significant funding for fisheries management. These are meaningful truths and any contributing factor — even a managed level of hydrilla — merits rational consideration.

More on this in a moment. For now, let’s look at the stellar fishery hosting the second Bassmaster Elite event of 2022.

AN IMPROVING FISHERY

Comprising eight main lakes — Apopka, Harris, Griffin, Eustis, Dora, Beauclair, Carlton, and Yale (the latter not included in tournament boundaries) — with approximately 75,000 acres, this Central Florida gem offers a good example of how vegetation positively impacts a fishery. Native eel grass, lily pads, flat reeds, Kissimmee grass, etc. paint a healthy picture of lakes rich with bass habitat and forage.

Spotlighting the caliber of fishery we’re discussing, the recent Strike King Bassmaster College Series presented by Bass Pro Shops saw brothers Lafe and Matt Messer of Kentucky Christian University win the event with a two-day total of 61 pounds, 13 ounces. The Messers broke the series’ two-day catch record, while their Day-2 limit of 36-7 broke the single-day record.

This week’s Elite event has produced plenty of quantity, as well as several quality catches in the 6- to 9-pound range. On Day 3, John Cox set the high mark with an 11-pounder.

Scott Bisping, FWC Fisheries Resource Biologist for the Harris Chain of Lakes, considers this collection of waterways some of the state’s best. Supporting this opinion, he points to the FWC’s TrophyCatch program, which recognizes three tiers of notable catches: 8-10 pounds (Lunker Club), 10-13 pounds (Trophy Club) and over 13 pounds (Hall of Fame Club).

“I’m pretty biased since I work and fish on this chain, but I think the Harris Chain stacks up pretty well with the other Florida bass fisheries,” he said. “We have been averaging around 70-80 TrophyCatch submissions annually over the last 5 years.

“The biggest bass we have documented and seen during our electrofishing sampling is around 12.5 pounds. Looking at our TrophyCatch data, the biggest bass approved into the program from the Harris Chain was caught on Lake Yale in 2020 and was 12-11.”

Bisping points to improved water quality and habitat as the main factors driving this fishery’s productivity.

“The Harris Chain has seen some major changes over the last 20 years,” he said of the fishery’s upward trend. “In the past, the Harris Chain has been very hypereutrophic (extreme nutrient levels causing vast algal blooms, oxygen depletion, fish kills) with poor water quality resulting in limited amounts of submersed vegetation.”

Fortunately, Bisping said, multiple restorations efforts by various management agencies, including key land acquisitions, stormwater treatment projects and a nutrient reduction facility located on the Apopka/Beauclair canal (Lake County Water Authority) have all played a role in reducing nutrients coming into the systems. 

“These reduced nutrients have improved the water quality and, in turn, water clarity and have created conditions that promote vegetation growth, specifically submerged vegetation,” Bisping said. “This vegetation serves as excellent nursery habitat that can help produce good year classes of bass improving the overall population.” 

A HELPING HAND

With over two decades of habitat and fisheries studies on the Harris Chain, University of Florida Fisheries Professor Mike Allen heartily agrees and notes that, despite hydrilla’s invasive status, this submersed vegetation has also contributed to the Harris Chain’s improving picture.

“From a fisheries perspective, I believe having that hydrilla in the lakes is not only going to (yield) more fish, but it’s going to create more habitat for native vegetation too,” Allen said. “Eel grass will grow in behind that stuff and now it’s protected (from major weather events), the water’s clear and it’s a better environment for native plants.

“I’ve seen the (Harris Chain) lakes in really bad shape, with very little plants and I’ve seen some of the lakes occasionally in good shape. I don’t know that, in my 25 years in Florida that I’ve seen them all be as good as they are right now.”

To this point, the Elite tournament has seen anglers disperse throughout the chain, but Lake Harris’ Banana Cove area has seen the greatest concentration of effort, including many of the top performers. One of the lake’s few areas of remaining hydrilla, this community hole on Harris’ east side consistently produces quality bites, largely because it holds the lake’s best bass habitat.

Looking south to the chain’s headwaters, Lake Apopka’s big bass wonderland was once considered Central Florida’s first tourist attraction (pre-theme park era). Sadly, many years of pollution, mostly from agricultural operations on the north end, so devastated the ecosystem that Florida’s fourth-largest lake became known as the Dead Sea.

Today’s Lake Apopka has experienced a dramatic turnaround and, over the past few years, the lake has reclaimed its status as a bass fishing Mecca. Spearheading this revival, the St. Johns River Water Management District and its partners have worked to restore wetlands, improve water quality and clarity by reducing phosphorus and suspended solids in the water and restore fish and wildlife habitats.

Hydrilla, while not welcomed by state agencies, has also flourished in Apopka. Allen said the approximately 11,000 acres of this submersed vegetation has played a contributing role in filtering the lake and promoting the clarity that benefits fish and native vegetation.

GRASS PLAN

And that brings us back to the initial premise. How much of a good thing should be allowed?

Stating the agency’s position, Bisping said: “FWC’s Invasive Plant Management section actively treats invasive plants in the Harris Chain of Lakes with the goals of minimizing impacts to access/navigation and promoting the growth of the ever-expanding native vegetation we are seeing within the Harris Chain. The primary invasive plants FWC targets in the chain are hydrilla, water lettuce, and water hyacinth.”

Noting this, Gilliland said B.A.S.S. recognizes the state’s responsibility to manage invasives and protect native plant communities. The only ask is that the facts of what benefits bass fishing remain on the table.

“The main thing that we’re always concerned with on any of these bodies of water is vegetation management — making sure that when the vegetation control plans are drafted that fishing, particularly bass fishing, is one of the key components that is considered,” Gilliland said. 

“We just want to make sure we’re heard and that our interests are being considered so, when there are herbicide treatments, that they are done in such a way to try to maintain as much good habitat as possible.”

Various Harris Chain user groups will likely maintain differing views of hydrilla. Everyone’s opinion matters, but Gilliland believes the goal should be management, not eradication. 

“A lot of people that live around these lakes want them to look like a swimming pool (with no submersed vegetation),” he said. “From a fisheries standpoint, that’s not the kind of balance we’re looking for.”

LESSONS FROM THE PAST

Don’t mistake Gilliland’s position for unfounded alarmism. The late-80s saw an all-out blitz of herbicides decimating not only the Harris Chain’s hydrilla but nearly all of its native vegetation. Since that disaster, aquatic plant treatment has advanced in thought and application. 

Nevertheless, watchful concern remains.

“As long as those treatments are controlled and done in such a way that it doesn’t impact the fish production and the quality of the fishing, we’re good,” Gilliland said. “We just have to be vigilant to make sure that our interests, from the fishing perspective, are part of the equation.”

Pragmatically, Allen points out the wisdom of a management plan that embraces hydrilla benefits, while limiting its negative impacts.

“Eradication of hydrilla in Florida is completely impossible and will never happen,” Allen said of this plant’s vigorous nature. “So the question is ‘How much are you going to allow?

“We need to acknowledge that it’s really good habitat and we’re not going to get rid of it. So, in my mind, the take-home is this: If it provides excellent fish and wildlife habitat — and I don’t think anyone argues it doesn’t — and eradication is not possible, then we’re in a scenario of ‘How are you going to manage it? How much does that management cost? And what are the benefits that result from that management?”

Having recently discussed Lake Apopka’s hydrilla situation with the FWC, Allen said he opposes large-scale herbicide treatments. In his view, the best course to achieve an equitable balance between productive fisheries and the interests of other user groups would involve precision treatments with contact herbicides to keep access points and primary boating lanes open throughout the lake.

Gilliland acknowledges that state agencies face the daunting task of seeking solutions that all satisfy multiple user groups. Further, there’s no implication that the needs of bass anglers should control the narrative. But going forward, B.A.S.S. will continue to advocate for management practices that fairly consider recreational fishing.

“As the population grows and the nutrients increase, it’s going to be a bigger and bigger challenge to maintain healthy balances of aquatic plants,” Gilliland said. “We just want a seat at the table. We want to make sure these systems are managed in such a way that we get our part of the consideration.”