Michigan Department of Natural Resources
Hillsdale County (T7S, R4W, Sections 3 and 4)
Surveyed June 1989
Michael P. Herman
Round Lake, 72 acres in size, is located in west-central Hillsdale County
approximately 6 miles west of the city of Hillsdale. It is part of the
St. Joseph River watershed. Little Hog Creek enters Round Lake from the
north, and a small unnamed inlet flows into the lake on its eastern side.
Round Lake has one small outlet on its west side which flows into Hemlock
Marl is the predominant substrate type from shore out to the 10-foot
contour and covers approximately 10% of the total lake bottom. There are
some scattered areas of gravel and sand near shore. Over 80% of this lake's
substrate is comprised of organic matter. Bulrush, white and yellow water
lily, and several species of pondweed are the most abundant aquatic plants
found in the lake; all are moderately abundant.
Round Lake has the steep drop-off characteristic of marl lakes. The maximum
depth is 36 feet, and approximately 85% of the lake's surface area is
deeper than 10 feet. Water color is best described as clear to slightly
turbid. The latest limnology survey (August 1980) found temperatures ranging
from 74°F at the surface to 45°F at the bottom. A thermocline
occupied the layer of water between the 16 and 21 foot depths. Dissolved
oxygen concentrations in this layer of water were high, ranging from 5
ppm to 9 ppm.
The shoreline is approximately one-third developed with about 30 mostly-permanent
residences. A state-owned public fishing site with a gravel boat ramp
was constructed on the northwest shore in 1964. The undeveloped shoreline
of Round Lake supports a mixture of wetland shrubs, green ash, and red
and silver maples.
An electrofishing survey in 1965 collected several game fish species
including bluegill, pumpkinseed sunfish, yellow perch, black crappie,
and largemouth bass. One 12-inch rainbow trout was also caught. It probably
immigrated from Hemlock Lake, which has been stocked with rainbow trout
since the mid-1950s. All game fish species caught in 1965 were reported
to be in excellent condition and fishing pressure was estimated as moderate.
Round Lake was last surveyed in June 1989 with four standard 6 x 3-foot
trap nets and two 125-foot experimental gill nets (Table 1). Game fish
species captured in descending order of abundance included bluegill (160),
black crappie (8), largemouth bass (6), pumpkinseed sunfish (5), and rock
bass (1). Although few largemouth bass were captured in nets, numerous
small bass were observed in the shallow areas of the lake.
Bluegills comprised nearly 70% of all fish caught in trap nets. Bluegills
averaged 7.1 inches each, were as large as 9.5 inches, and over 80% of
them were of an acceptable size to anglers. Bluegills over 8 inches long
are generally uncommon in most other area lakes and bluegills larger than
9 inches are rare.
Bluegills are targeted for sampling in inland lakes because of their
role in determining fish community structure and overall sportfishing
quality (Schneider 1981). Even though the goal of lake surveys is to sample
all fish species and all sizes present, many times the bluegill population
is the only one adequately sampled because bluegills are typically the
most abundant. A ranking system was de- veloped recently that allows fish
managers to get an idea of the relative quality of a lake's fish population.
On a scale of 1 to 7, (Schneider 1990), the quality of the bluegill population
in Round Lake was calculated as 5.8 or "excellent".
Based on growth analysis using fish scales, bluegills caught during the
1989 survey exhibited growth rates above the state average (Table 2).
No yellow perch were caught in trap nets, but this species comprised
over 70% by number and 66% by weight of the total gill net catch (Table
1). Nearly 90% of all perch were of acceptable size to anglers. They averaged
8.5 inches each, and were as large as 12.6 inches. As a group, they exhibited
a growth rate that was 1.0 inch above the state average (Table 2).
Black crappie and pumpkinseed also exhibited above average growth trends.
However, largemouth bass grew slowly. These conclusions are tentative
because they are based on small samples.
Age composition and survival characteristics of bluegill and yellow perch
populations appear to be normal based on scale sample frequencies (Table
3). Ages II through VIII were well represented. Only four age-V yellow
perch were caught during the 1989 survey, which suggests that a weak year
class may exist. Few age-II fish of either species were caught in trap
or gill nets, because small fish are much less vulnerable to netting.
The catch from the 1989 survey shows that a good species mix exists in
this lake. Bluegill and yellow perch growth rates and average sizes are
impressive, suggesting that these two species may be under-utilized by
Anglers interviewed during the 1989 survey reported good open-water fishing
success for bluegill and crappie, but poor success for bass. Ice fishing
was rated as good, but fishing pressure was only light. One angler reported
that good perch fishing opportunities existed in Round Lake while others
were unable to catch this species consistently.
Round Lake presently supports excellent populations of yellow perch and
bluegills for angling. A water chemistry survey of Round Lake in 1980
showed that temperatures and dissolved oxygen levels favorable for rainbow
trout growth and survival existed. This data, together with the absence
of northern pike, make this lake a good candidate for the introduction
of rainbow trout. An updated dissolved oxygen and temperature profile
of Round Lake is planned in the summer of 1990. If water quality is found
to be comparable to the 1980 data, it is recommended that rainbow trout
be stocked to provide an additional angling opportunity. Subsequent surveys
of this lake's fishery should be made to evaluate trout growth and survival
as well as to monitor the growth rates of existing game fish.
Report completed: March 9, 1990.
Schneider, J. C. 1981. Fish communities in warmwater lakes. Michigan
Department of Natural Resources, Fisheries Research Report 1890, Ann Arbor.
Schneider, J. C. 1990. Classifying bluegill populations from lake survey
data. Michigan Department of Natural Resources, Fisheries Technical Report
90-10, Ann Arbor.
Table 1.-Number, weight, catch per effort, and percent legal size
for species of fish taken with trap or gill nets from Round Lake, June
Table 2.-Average total length (inches) at age, with ranges, for
bluegill and yellow perch taken with trap and gill nets from Round Lake,
June 9, 1989. Number of fish aged in parentheses.
Table 3.-Percentage age frequency for two species of fish taken
with trap or gill nets from Round Lake, June 9, 1989 (number of fish in
Last Update: 08/06/02