The Big O’s water woes

One of the common themes we’ve heard during the Elite season-opener on Lake Okeechobee has bemoaned the diminished playing field.

One of the common themes we’ve heard during the Elite season-opener on Lake Okeechobee has bemoaned the diminished playing field. Less filtering vegetation — mainly hydrilla and eel grass — than we’ve seen in previous visits has minimized the clean water that bass prefer, particularly during the spawn.

A common assumption assigns blame to herbicide treatments used to eradicate invasive plants such as hydrilla that interfere with native species. However, Matt Stevens, Lake Okeechobee biologist with the Florida Fish and Wildlife Conservation Commission, offered clarifying insight that helps frame the big-picture reality of Okeechobee’s challenges.

For starters, while the FWC has, at times, utilized herbicides for aquatic plant control on prominent bass fisheries, including Lake Okeechobee, Stevens said that has not played a significant role on the Big O in recent years. We’ll explain this next part shortly, but to say Mother Nature has deeply impacted this lake’s water quality is no exaggeration. 

“The hydrilla that was in the Harney Pond Canal area and Fish Eating Bay, we lost that during Hurricane Irma (2017) and that grass hasn’t returned,” Stevens said. “We haven’t treated any hydrilla on the lake since 2015 and the last time we treated hydrilla, that was a navigational canal that was starting to get choked out and we had to open it up for access. 

“And we do not ever treat eel grass, pond weed, naiad, and any of the native submersed plants.”

That being said, Stevens acknowledges Okeechobee’s filtration issue. Riding around the lake, you’ll still see a good amounts of reeds, pads and other plants that reach above the surface. The problem, however, originates below the surface. 

“It’s true, we don’t have as much filtering vegetation, which we refer to as SAV — submersed aquatic vegetation,” Stevens said. “That’s the vegetation you cannot see while you’re fishing. Emergent vegetation is your cattails, buggy whips, Kissimmee grass and things like that. 

“The submersed grass is really important for water clarity, it’s important for juvenile bass, it’s good rearing habitat, so it’s really important for the lake.”

So, what accounts for the decline of Lake Okeechobee’s SAV? As Stevens explains, understanding the present requires a look to the past.

Keeping Track

According to Stevens, the South Florida Water Management District started tracking SAV in 2003. Why then? Well, picture of a bowl of M&Ms. Do you count them when the bowl is full or when a noticeable decline makes you wonder how many remain? 

Abundance fosters apathy. It’s not a lack of caring; rather, it’s the absence of concerning stimulus.

As Stevens notes, Lake Okeechobee averaged over 100,000 acres of SAV prior to 2003. That number is down to about 3,000 acres.

“We had so much SAV until (the early 2000s) that we never really needed to keep track of how much we had and how much we needed,” Stevens said. “When you have plenty of something, there’s really not a need to always count it.

“As we started tracking SAV, along with water levels in the lake, we see that whenever we have high water periods of 45 days or longer, we start to lose vegetation.”

While the FWC manages Lake Okeechobee’s habitat and wildlife, the U.S. Army Corps of Engineers, along with the Southwest Florida Water Management District controls the water. 

We won’t digress into topics covered elsewhere, but as Stevens explained, water management policies of the 1990’s saw Okeechobee holding a lot of water for municipal supply, irrigation and flood control. 

Recent years have seen several hurricanes dumping huge volumes of water on, not only South Florida, but also the state’s central region. With Okeechobee receiving water from the entire Kissimmee Chain of Lakes via the Kissimmee River, those tropical deluges that swell normal precipitation levels, head south to the state’s perennial catch basin.

Tropical Troubles

Describing the present chapter of an ongoing tale, Stevens said: “When the lake came up (approximately) 4 feet in the fall (after Hurricane Ian, Sept. 30; then Hurricane Nicole, Nov. 10), visibility was only about a foot to half a foot, so when you put 4 feet of water and that low visibility on top of that vegetation, you take away the sunlight.

“Plants need sunlight to survive and when we cover them with (several) extra feet of water for more than 45 days — now (as of Feb. 17) we’re over 100 days over 15 1/2 feet — we’re definitely losing vegetation on a daily basis because it’s getting clouded out by all the high water.”

Stevens said Lake Okeechobee went from about 12 1/2 feet to 15 1/2 feet after Hurricane Ian. Nicole’s impact pushed that number to about 16 1/4, but the water level pulled back to about 16 by January and stood at 15.8 at the tournament’s start.

Putting into perspective, the amount of water Okeechobee received since Fall 2022, Stevens offers a relevant comparison: “In the summer of 2022, we did a drawdown on Lake Kissimmee (lowest in the chain) where we took the lake down 2 1/2 feet. When we took that water into Lake Okeechobee, we only came up 1 inch.

“When you think about 4 feet of water from Hurricanes Ian and Nicole, that’s a ton of water, so it’s obviously going to make the lake turbid and there were high winds that muddied the water up. If you don’t come down right away, like the lake used to naturally, that turbidity sticks around and we lose vegetation week after week, day after day.”

Stevens points out that herbicides remain one of the habitat management tools at the agency’s disposal; however, it’s wielded with purposeful discretion. Modern technologies and chemicals, he said, allows for more targeted treatments with smaller doses.

 “We really hate to see (the SAV) going away, but the high water has been what’s knocking it back. A variety of plants always makes for a lot better habitat, Stevens said.

Ideally, that’s the picture the FWC would prefer to see throughout Lake Okeechobee. For the time being, diminishing habitat remains a daily challenge on the state’s biggest lake, but Stevens’ goal is to communicate the facts about how and why it’s happening.

 Stevens concluded, “I have to say though that the lake is still amazing and one of the best fisheries in the world. Despite its issues, Okeechobee is still showing out as a premier bass fishing destination.”

B.A.S.S. Conservation Director Gene Gilliland contributed to this report.