Sunday, March 26, 2017

Changes on the Bay

Every year brings new surprises, or a return to familiar features of the Laguna Madre system. From our narrow, anxious perspective, it's easy to believe that one year points to the next, and that degraded areas of the lagoon may portend a tilt away from clarity and fertility. I recall that not long ago, the brown tide would bloom each winter-spring, and the clarity of the water could be degraded by the brownish orange algae. Indeed, many pronounced the end of clear water, and a shift toward a 1000-year cycle of turbid conditions. And went away. Or at least it comes and goes without seizing the entire bay system.

About eight years ago, there was a hurricane that went into Mexico about 100 miles south of the Rio Grande. While it barely impacted us on landfall, the torrential rains that fell in the Mexican mountains--30 inches in a shorter period of time--rushed downstream and filled Falcon Reservoir so quickly that a crisis ensued. The dam was opened and the two floodways of the Rio Grande Valley that normally divert flood waters from overwhelming the Rio Grande cascaded into the Arroyo Colorado, and then into the Laguna Madre. For months, smelly river water clouded the normally pristine lagoon, and alligators, carp and other freshwater species came into estuary for most of the summer and beyond.

At that time, the turtle grass was literally replacing the shoal grass, and biologists predicted that the LLM would soon see a climax growth of turtle grass. And yet, after the fresh water flood, the turtle grass died off along with a lot of the other species as the fresh water, and lack of sunlight choked off the hypersaline species.

It has taken several years before areas adjacent to the floodways, such as Paytons Bay (north of the Arroyo Colorado), returned to their former selves.  And now it seems that the seagrasses are developing in areas that have been devoid of vegetation for many years.

When I guided the other day, I saw seagrasses in flood-vulnerable west-side locales where I haven't seen them during the spring in almost a decade. It could be that a combination of warm winters, and time since the Mexican flood, combined to produce this seagrass recovery, but it's clear for anyone to see. Indeed, I poled my client Alec along a shoreline last Sunday that has been bereft of seagrasses for years, even though the venue is nonetheless one of the most productive shrimp nurseries for the brown and white shrimp populations.  During many years, the grasses are nonexistent early in the season, and only by June and later does one find well-established seagrass in many of the west-side lagoons. At the rate of seagrass growth this spring, the bay should be grassy in most areas by early summer, creating the conditions that flyfishers love to see in mid-summer---extremely low tides, and crystal clear water.

Alec saw pods of redfish in about 9 inches of water, as well as dozens of larger singles and pairs feeding aggressively in the clear, grassy conditions. Shrimp leapt out of the water, and an occasional gull would swing into place over the feeding fish, even though the low winds made it impossible for them to hover in place for long.

Alec was relatively inexperienced as a flyfisher on the LLM, but he landed two nice reds before we moved on.

What we didn't find in our explorations were fish on the sand. Indeed, I went east around 9 am, and then again during the afternoon, and the sand was barren. We ended up going in a bit earlier than usual because the wind "blew out" the water clarity on the west side, and there simply no fish to be found on the east side, where you need them during midday and beyond.

When I spoke a good friend later in the day, he confirmed my suspicions that the fish were feeding late on the east side. He said he'd been "surrounded by reds" the previous evening. As you know, I've been talking about the late action in several of my previous posts, and in my latest article in Tide magazine, as well. There are several reasons the reds have shifted to later, east side feeding, but we do know that when the seagrasses died on the west side, they began to proliferate on the east side, creating attractive conditions for shrimp, which historically have gravitated to the vegetation on the west side. Add to that the daytime boat traffic in the central part of the LLM, and you have perfect conditions for nighttime, east side feeding.

I don't mind you knowing, because most guides do not stay out that long, and if you're a local flyfisher who's willing to go out just before dark, you're one of the few, and you deserve to know.

No comments: