Largemouth and Smallmouth Numbers Soar
by Thomas Brooking, J. Randy Jackson, and Anthony VanDeValk, Cornell Field Station
Many walleye and perch anglers have discovered the excitement of hearing their reels' drags scream when a smallmouth bass hooks up and streaks for mid-lake. Often, the fish rockets from the water in a body-shaking leap, creating the ultimate Oneida Lake anglers' adrenaline rush. Smallmouths inhabit the lake's rocky shoals and also live in shoreline areas that have both rocks and weeds. Their largemouth cousins prefer dense, weedy locales, often with softer bottoms. Bays and marinas provide ideal habitat for the latter bass. Large numbers of both bass thrive in our lake, creating superb angling opportunities.
In recent years, when walleye and perch numbers have tumbled, bass have become a more popular quarry. Smallmouths, or "bronze-backs" in the vernacular, and largemouths, are Oneida's third most pursued species. Data recorded by the Cornell Creel Survey of 1997-98 and by the Angler Diary Program from 1994-99, clearly show this.
We estimated smallmouth bass abundance from the catch of adult bass in our gillnets. The Field Station has used these standard nets since 1958. We set the nets at 15 sites around the lake during the Summer. The smallmouth bass catch in our nets has increased substantially since the mid-1980's. The number of smallmouths we netted in 2000 was nearly three times the amount we captured in 1985!
This increase agrees with a similar rise in the number of young smallmouths that hatched in late Spring. We catch the young each summer in our trawl nets. These nets are towed, along the bottom, at 10 sites every week. You may have seen our large, red trawling boat with "Cornell" printed on the side. The catch of young bass has jumped since the mid-1980's. For example, the 1994 hatch was 3.8 times larger than the largest hatch recorded from 1958 to 1990! This is excellent news for bass anglers and indicates that the smallmouth population is thriving. Changes during the last decade, such as the zebra mussel invasion and reduced phosphorus levels, have not negatively affected bass.
We can only speculate on why smallmouth numbers have increased. Bass are a "sight feeding predator" and Oneida's clearer water helps them find prey. Historically, smallmouths are known for inhabiting clear, pristine lakes. Smallmouths may also be helped by the lake's increased aquatic vegetation. In addition, fewer walleyes in Oneida probably means less competition for bass for available forage. Finally, increased abundance of white perch and gizzard shad provide additional prey for bass. The good bass hatches of the 1990's should sustain the population at a high level for at least several more years.
What About Largemouths?
We don't have as much information on "bucket mouths". They are primarily found in thick weeds and we seldom catch them in our nets.
We remedied our data drought by attending several bass club fishing tournaments during August of 2000. We collected age and growth data on a few of the largemouth bass. We checked 70 largemouths at the South Shore Boat Launch and 46 at the Oneida Shores County Park. Fish were weighed and measured. Scale samples, used to age fish, were also collected.
Anglers caught a lot of big bass. Out of the 116 largemouths we checked, 44 weighed over 3 pounds. Four of these tipped the scales at over 5 pounds! There are obviously some lunker largemouths living in Oneida.
Lake-Wide Bass Movements
In the late 1950's, Dr. John Forney examined smallmouth bass growth, movement, and survival. In that study, smallmouths were tagged and released just prior to the 1954-1958 fishing seasons. Most tagged fish remained within 1-2 miles of where they were tagged. This is what we call a "localized" population. When Forney moved bass from netting sites to distant release points (up to 15 miles away), the majority of the fish returned to their home areas. Little movement of fish occurred between bass tagged at Constantia and Shackelton Shoals, although these places are separated by only 3 miles. Forney also found that from 5-21% of the lake's bass were caught by anglers yearly. Later, he discovered that most young bass fingerlings were produced in years with the warmest June air temperatures. Bass growth was greatest in years that boasted good hatches of yellow perch.
How Fast Do Bass Grow?
A fish's age can be determined by examining scales under a microscope. Many fish have growth rings on their scales, similar to rings in a tree, though not as clear. We can determine how many winters a fish has lived through by counting these rings.
The chart below shows the average length of Oneida Lake smallmouth and largemouth bass after each growing season. For example, a 2 ½ year-old smallmouth is, generally, about 9 inches long. A largemouth that is 18½ inches long is probably 11½ years old! Smallmouths grow a little slower than largemouths. Any smallmouth from Oneida that exceeds 16 inches is at least 8 years old.
Many Oneida Lake bass live more than 10 years, and the largest ones live more than 14! Smallmouths are growing faster now than they did in the past. Fingerling bass are larger at the end of their first summer, and the growth rate of young adults has increased in the past 5-10 years, compared to bass that lived from the 1950's to the 1980's.
These changes are probably due to some of the larger changes in the lake. Again, increases in water clarity, abundance of weeds, and more available forage probably benefit bass.
A Bass' Preferred Menu
Stomach analyses of adult smallmouth bass revealed that the most commonly ingested items were crayfish (47% of diet items), small fish and minnows (41%), and aquatic insects (13%). Fingerling smallmouths eat mostly insects, plankton, and some minnows. Adult largemouth bass consume primarily smaller fish. They dine on whatever forage species is most readily available. They are opportunistic feeders, however, and also gorge on insects, invertebrates, amphibians, and even bite-sized mammals.
Where are the Bass?
Try any stone-bottomed area of the lake for smallmouths and the shallow, weedy, mud-floored bays for largemouths. Marinas and their adjoining waters are also good largemouth spots. Shallow, rocky reefs, surrounded by deeper water, are particularly good areas for smallmouths.
The bait and tackle shops near the lake are libraries of fishing knowledge and can hook anglers up with the latest in lures, baits, and tackle options that appeal to Oneida Lake's booming bass population.