Date: April 11, 2019 Author: Georgia DNR, Wildlife Resources Division 0 Comments
Spring is the season of new life. For many fish species, this means it’s time to get moving. Check out a few of Georgia’s natives who migrate to a new area for spawning!
Fisheries Technician Collin George holds a lake sturgeon caught on the Etowah River.
These dinosaur-like fish spawn from late April to early June. They migrate upstream to find shallow, rocky spots along the bank. The male will arrive first and wait until a female reaches the same spot. The female will swim and release hundreds of thousands of eggs. The male swims beside her, simultaneously releasing their sperm. The fertilized eggs fall to the riverbed and attach to rocks and other solid material before hatching five to eight days later.
White bass caught during broodstock collection in the Coosa River Basin.
Starting in mid-March, as water temperatures begin to reach 50 degrees Fahrenheit, the white bass spawn run begins. Males head to tributaries and headwaters to search for suitable habitat. They prefer areas above and below shallow runs, shoots, and shoals because there is just enough current to prevent sediment from building up. Females follow weeks later and pick out a clean rock, gravel, or wood surface. When the female releases her eggs in her chosen location, multiple males gather to release their sperm. Depending on both her age and size, the female may produce anywhere from 200,000 to 300,000 eggs. The adhesive fertilized eggs attach where they’re deposited. They will incubate, then hatch about 48 hours later.
Fisheries Biologist Zach Moran holds a walleye collected for hatchery broodstock.
When water temperatures get warmer, and the days become longer, it’s spawning time! From late February to March, walleye make their yearly run to shallow, rocky headwaters. Males wait patiently at the spawning grounds for a “ripe” female to arrive. When she makes her debut, the males rush to her. As the males push each other with their fins and noses, the female is turned on her side and releases her eggs to be fertilized. Walleye don’t guard their eggs; instead they return to deeper water after spawning. Water temperature dictates how fast the eggs hatch—the warmer the water, the faster they hatch.
Fisheries Biologist Zach Moran holds a roughly 40 pound striped bass caught on Nottley Lake.
From April to June, when water temperatures begin to exceed 60 degrees, striped bass are spawning. The mating ritual of these fish is quite a sight to behold and is often called a “rock fight” due to the commotion. A group of males will surround a female and push her to the surface of the water until she releases eggs. Males then release sperm, and the fertilized eggs will drift with the current. After hatching, the larvae continue to drift, munching on microscopic animals until they reach the nursery area. The nursery is usually a river delta or inland coastal sound. The juveniles will stay here to mature for two to four years and then head out to deeper waters.
Female (top) and male (bottom) American shad.
American shad have a very difficult spawning ritual compared to other native fish species. They are anadromous, which means that they live in salt water, but they spawn in freshwater. Using their sense of smell, shad leave the ocean to find the place they hatched. When they reach their spawning grounds, the males and females release their sperm and eggs in the water column. The eggs are carried by the current until they hatch. Each shad only has one spawning season. The energy it takes to make the journey and reproduce leaves them exhausted and unable to survive. Some individual fish in more northern populations may be able to make many spawning runs, though.
Angler holds shoal bass caught on the Chattahoochee River.
From late March through mid-May, shoal bass are seeking rocky “shoal” habitat for spawning. These fish begin their search for spawning sites when water temperatures rise above 59 degrees Fahrenheit. High-flow events that occur after heavy rains in the watershed also appear to trigger spawning. The eggs will hatch, on average, 4-6 days later. Like walleye, incubation periods are temperature-dependent. Research has shown that some shoal bass, particularly those in the Flint River, move more than 50 miles to their preferred spawning sites, while others stay closer to home and spawn near areas where they live the rest of the year.