Thursday, June 27, 2019

Excitement Over a Shimmering Shiner (actually tens of thousands of them)

Jim taking it all in (click to enlarge)
Q: How have three weeks gone by since my last post?!
A: Continued historic high water (leading to daily vigilance in observing water levels within the marsh to detect and repair inevitable leaks); pressing for clearance from the USACE for the green light to start another dike rehab project (see aforementioned leaks -- I'll write a dedicated post on this very soon); tying up the loose ends from our first GLRI-funded project; prepping for our second GLRI-funded project; tours; meetings; another cooperative management agreement with ODNR Private Lands; more work on our WRE easements (East and West); and, of course, more fish!

Yep, it's been a busy month of June.

It's always difficult to recap a day in the marsh -- much less a week . . . or multiple weeks. So I'll just try to hit some high points. And per usual, I'll try to share representative images to help tell some individual stories.

The first is one we're particularly excited about because it's yet another example of "if you build it, they will come."

A little over a week ago we were hosting a group of a dozen or so biologists, ecologists, and water chemistry experts. Our tour ended at our new pump and water conveyance structure. Just as we were talking about the attributes of the "fish-friendly" design, Roy looked over the guardrail and noticed something we've never seen before . . .

Tens of thousands of shiners along with a "slurry" of juvenile fish <1" long had congregated in the 50-foot flume of our new structure. Although the pump had been running for several days with nothing but the occasional and isolated school of juvenile mosquito fish visible, something cued this mass concentration.

The emerald shiner is a favored baitfish, not only by fishermen,
but more importantly by yellow perch, walleye, bass, crappies, 
and any other predatory fish in Lake Erie
As soon as we concluded the tour, we were one the phone with our good friend Jim Johnson. As a Bay View native and lifelong outdoor enthusiast, Jim grew up hunting, trapping, and exploring the marsh. (I've written of Jim before because he is a true marsh lover and is our lead punter on the West Marsh.) Jim also happens to be a licensed commercial minnow fisherman and bait store owner who has seined and dipped for emerald shiners on Lake Erie for more than three decades.

Jim's truck arrived in a matter of minutes. Quite simply, he was awestruck. Jim confirmed what we suspected. The shiners were largely "emeralds" (with a few spottails mixed in for good measure) and they were there to spawn.

Moving water is a primary draw, but other factors like water temperature, photoperiod, water clarity, water chemistry, and even lunar cycle can all play a role in increasing numbers. It's always fun to see such a concentration of life. But it is particularly exciting with the context that emerald shiner populations have been on the sharp decline throughout Lake Erie for the better part of a decade.

These emerald shiners were dipped from within the structure
just long enough to be positively identified and then
were promptly released (unharmed)
Jim said he hasn't seen a congregation like we've witnessed (much less a spawning event) in years. He was so enthusiastic about seeing the phenomenon -- which lasted the better part of a week -- that he was more interested in sitting and watching than filling his nets, mobile tanks, or bait shop (even though he was running low). Reality is, we were all just content to sit and watch the shimmering ebb and flow of life . . . with smiles on our faces.

(1) To read more about the decline in the emerald shiner population on Lake Erie, check out this article from my friend, John Hageman. Contributing factors may be high predation from historically large populations of walleye and yellow perch; high susceptibility to a viral disease called VHS (Viral Hemorrhagic Septicemia); increasingly volatile spring wind events (notably Superstorm Sandy in 2012); and potentially even mortality related to harmful algae blooms (HABs). Another reality though is that some populations tend to go through natural cycles. Here's to hoping Standing Rush can be contributing to an upturn!

(2) It turns out that the smattering of "little fish" in the structure are a mix of species that have hatched in our adjacent estuary or the open bay over the last several weeks. So far, I've confirmed white perch (and probably white bass), bluegills, crappies (probably both white and black), gizzard shad, and carp. I would suspect there are also walleye and probably a handful of other species. Interestingly, as recently as yesterday, only a few isolated shiners were visible in the structure -- now replaced by clouds of tiny (0.5") yellow perch. As I left yesterday, a solid mass of juvenile yellow perch covered an area 6' wide by about 20' long and were packed in from the surface to at least a depth of 2' -- where turbidity prevented visible confirmation at greater depths. If the entire water column (now about 6' deep) was full of these tiny fish, again, it would be safe to say there were tens of thousands just within the structure itself.

Even as the clear marsh water mixed with the wind-churned turbidity of bay water, the shiners put on a show
for the GoPro (each of these shiners is about 3-inches long)

More fun GoPro footage --don't miss the others lurking in the murky depths!
(Spoiler Alert: Sheephead and Largemouth Bass)