Standard summer sampling was conducted in 2007 to monitor population trends of

the reservoir's fish community, particularly walleye and crappie. This sampling

effort, which generally consists of twelve gillnet and four trapnet sites, has been

conducted regularly since the mid-1980's. This year, because walleye catch rates

were so high, sampling effort was reduced to nine gillnet sites to limit further walleye

mortality.

The gillnet catch rate of walleye (12.3/net) surpassed the previous record high of

11.6/net observed in July 2005. For perspective, gillnet catch rates of walleye in the

1980's averaged around 1/net, and then jumped to 3-4/net in the 1990's. Gillnet

catch rates for walleye in this decade have averaged over 10.5/net during 3 of the 4

sampling years and was 5.3/net in the fourth (2003). Numerous walleye yearclasses

were represented in the sample, with sizes ranging from 11 to nearly 26 inches.

Recruitment of walleye via natural reproduction has been consistently high since the

mid-1990's. The reason for the increased production is not clear but crappie

populations have generally been at a lower levels during this same time period.

Age 2+ white crappie were well represented in the trapnet catches. The occurrence

of these fish marks the first decent year of production in more than half of a decade.

The crappie population has been depressed for a number of years with the last fairly

strong yearclass having been produced in 2000. The catch rate of crappie in gillnets

was relatively low so it is hard to say whether the 2005 yearclass is large or simply

moderate in size due to the conflicting information between the two sampling gears.

Either way their growth appears good with the average falling somewhere in the

180-190mm size range. This represents nearly an inch of growth from the fall of

2006 when this yearclass averaged roughly 165mm in length (see survey 706004).

We anticipate that this yearclass should support good fishing beginning in winter

2007/2008.

Fall night electrofishing was conducted along the Whitney Point Reservoir shoreline

to monitor year class strength of walleye. Only two of the four standard sites were

sampled due to warm water temperatures and an earlier than normal lake

drawdown.

A total of 292 young of year (YOY) walleye (2007 year class) were captured in just

over 1.5 miles of shoreline shocked. Searns' (1982) formula for estimating

population size gives an estimated 52,831 YOY walleye present in the reservoir. This

is the fourth highest estimate of YOY walleye abundance in the 13 years of sampling

that have occurred since 1994. This is likely a conservative estimate because the

catch rate in site 2 is generally the lowest of the four standard sites. Sites 3 and 4 on

the west shore generally produce as many or more yearling than site 1 (215 of the

292). This yearclass could easily have rivaled the second largest we have seen

(71,000 in 2003).

The average length of YOY walleye was approximately 200mm (7.9 inches). This

average length is larger than YOY from recent years but comparable to young fish

captured in the 1990's. The largest walleye captured measured 504mm (19.9

inches) and weighed 1174gr (2.6 pounds).

Good numbers of white crappie were also collected during this effort. Age

determination has not yet been conducted but these fish are almost certainly part of

the strong 2005 yearclass. Sampling conducted in July 2007 indicated the average

length of this cohort to be approximately 185mm (7.25 inches) while only three

months later they are averaging approximately 225mm (8.9 inches) and were about

double the weight. This exceptional growth appeared to be the norm for most of the

reservoir's fish indicating that forage was abundant this summer. Indeed young of

year yellow perch, though not collected, were very abundant during this survey and

juvenile white crappie were also common.