# Growth rate for saugeye



## Mark Hicks (Apr 15, 2006)

Anyone know the growth rate for Ohio saugeye,need to know how many inches per year they grow


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## crawdiddy (Apr 10, 2006)

they grow a lot quicker (in terms of lenth) when they are small/young

in general they grow very fast.

stocked as as finglings I believe they will reach 16"-18+" in 5 years depending on how optimal the growing condtions are

once they get older their growth rate (length) slows way down and they start getting "fat"


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## fishdealer04 (Aug 27, 2006)

Yeah someone else asked this question awhile ago...if you do a search you might be able to find it. Basicly I think its 3 inches or so per year when they are young, and once they get to 17 inches or so it slows down and like crawdiddy said they start to get fat.


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## Corey (Apr 5, 2004)

Saugeye, at this Latitude have a very good growth rate. They average 6" per year for the first 3 years and then slow down. A 16-18" fish is 2 full years old. Remember though that this is an average and there are big 'uns & little 'uns just like with people. At the top end, they can reach as much as 27" in 4.5 years.


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## crawdiddy (Apr 10, 2006)

"Saugeye, at this Latitude have a very good growth rate. They average 6" per year for the first 3 years and then slow down. A 16-18" fish is 2 full years old. Remember though that this is an average and there are big 'uns & little 'uns just like with people. At the top end, they can reach as much as 27" in 4.5 years."

I think the answer "in general" lies somewhere bw my post and yours.

I just don't see "generally speaking" a fingerling getting to 17" after 2 years "in general in ohio".

I should probably just google "saugeye growth" but I'm too tired from yesterdays game festivites.

Did anyone see that football game that was on?


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## Corey (Apr 5, 2004)

I'm not guessing, just trying to pass along some info. These growth rates have been recorded for years by every State that breeds and stocks Saugeyes; Ohio, North Dakota, Nebraska, Oklahoma, Kentucky, et al.. The study done in Ohio is "Habitat Preferences, Survival, Growth, Foods, and Harvests of Walleye and Walleye X Sauger Hybrids" by Barry L. Johnson, David L. Smith, and Robert F. Carline; Ohio Cooperative Fishery research Unit, Ohio State University, Division of BioSciences. Published in the North American Journal of Fisheries Management 8:292-304, 1988.


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## crawdiddy (Apr 10, 2006)

I believe you I'm just going off of well, nothing much more than what I thought I knew.

They grow faster than weeds!


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## Corey (Apr 5, 2004)

Amen! Glad they do!!


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## crawdiddy (Apr 10, 2006)

me too!

that reminds me, aren't we getting to "about that time"!!!?  :B :B :B


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## Corey (Apr 5, 2004)

Been that time for weeks!!! Big fish comin' from Tappan, Clendenning and Salt Fork. Not a very dependable bite yet but plenty of good fish when you hit it right. I usually hit Piedmont pretty hard this time of year but I can't seem to tear myself away from Salt Fork this year.


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## crawdiddy (Apr 10, 2006)

I've been hitting up Griggs/Oshay spillways. FOr all my efforts all I have to show for it was getting to see a HUGE PIGBEAST. I thought I had snagged a log and was just reeling in it. THen 5 feet from me it surfaces and I'm like HOLY CRAP! I'm thinking a FAT 26", possibly even 28"+. This thing was huge. It had the profile of one of those subway party subs, glowing eyes and looked like it was gonna eat me!!!


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## Mark Hicks (Apr 15, 2006)

Thanks fo all imfo.keep fishing


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## acklac7 (May 31, 2004)

Was going to post earlier, then I realized I lost the link to the field study(same one Corey noted)..Luckily I found it again (Only to find that Corey had already mentioned it a similar study LOL)

At any rate here is a small excerpt: 



Survival said:


> Mean total length at the end of the second year varied little (approximately 284 mm) and growth was slow due to low abundance of prey.



It should be noted that this study was conducted in 3 small ponds, which lacked the primary growth stimulant for many S-eye: Shad (IMO)

Im not an expert..(yet)  But I would have to think the abundance of Shad located in our river/reservoirs causes S-eye to grow much faster than those noted in the study. Think about it, you got thousands of shad dieing off every winter, those S-eye are going to have an easy FEAST on those shad. While the S-eye in the ponds will have to chase minnows/shiners/bluegill around for a meal. Consequently the pond fish will eat less, resulting in decreased growth rates.

Just a thought 

EDIT: The quote above came from a different study than Corey mentioned. However it does show that (pond raised) S-eye average about 6" a year. 

Corey,I can't access the entire article, do you have it saved somewhere? I read the abstract and it noted that the study was conducted at Pleasent hill. Be interesting to compare the growth rates between the two studies, Maybe im wrong.


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## crawdiddy (Apr 10, 2006)

does anyone remember the in fisherman article on River eyes from a few years back? They make reference to one of our rivers here in town. And I believe cited some growth rate #'s. There was a picture of that dam that resides next to the bogey inn.


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## Corey (Apr 5, 2004)

At one time I had nearly every study done relating to Saugeye sent to me by a contact at OSU Div. of BioSciences. He was a graduate student who had been involved in the 1986 Hearns study on Saugeye reproduction. He's since gotten his Doctorate and moved on and I no longer have a contact there. I made the mistake back then of lending the studies out and some never came back. I don't lend them out anymore but let customers sit and read them if they have the interest. Membership on sites where hese are available is expensive so, like you, all I can access now are the abstracts for the ones I no longer have. I do have the one you want though but it's far too long to retype. As far as growth rates the 1979 year class Saugeyes stocked in Pleasant Hill reached an average of 555mm by Fall 1982 with weights averaging 4.25 pounds (1,902g). The Pleasant Hill study is interesting because they stocked both Walleye and Saugeye and did studies on both to determine differences in habitat preference, growth rates, etc. The growth rate of Saugeyes has been higher than that of Walleyes in this and every other study I've found. If you ever get a chance to stop by the shop you can check out the study. I also have a bibliography listing many other Saugeye related studies.


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## Corey (Apr 5, 2004)

acklac7, I took the time to retype the study for you.

*Habitat Preferences, Survival, Growth, Foods, and Harvest of Walleye and Walleye X Sauger Hybrids*​_Abstract_.- We compared habitat preferences, survival, growth, foods, and harvests of stocked Walleyes _Stizostedion vitreum _ and Walleye X Sauger _S canadense _ hybrids in Pleasant Hill Reservoir, Ohio. Both fishes were stocked at similar rates and sizes (about 40mm mean total length) in late May or early June 1979-1982. Neither group showed consistently better survival. Growth was similar until age 2. Thereafter, hybrids grew faster than Walleyes. Age-0 Walleyes occured mostly over fine substrates in early Summer and coarse substrates by Fall. Habitat selection by age-0 hybrids was similar to that of Walleyes, except hybrids preferred finer substrates in Fall. Older hybrids and Walleyes moved offshore at temperatures above 22 degrees C. Diets of both fishes were similar, but hybrids ate more littoral fishes, where Walleyes ate more pelagic fishes. Age-1 and older hybrids and Walleyes ate mostly invertebrates in Spring. Age-0 Gizzard Shad (_Dorosoma cepedianum_) were the most important prey for all age of both groups. Hybrids and Walleyes were caught by anglers in proportion to their abundance and contributed most to the fishery at ages 1 and 2. Hybrids have the potential to breed with either parent species and may introduce new genetic material into existing Walleye or Sauger populations. Data from our study and other Ohio waters show that hybrids can support important fisheries, particularly in tailwaters, and may be more successful than Walleyes in impoundments with short water-retention times.


Walleyes, _Stizostedion vitreum _ are highly desirable gamefish, but in many waters they do not reproduce (Laarman 1978; Prentice and Clark 1978). Consequently, many Walleye management programs rely heavily on stockings to maintain populations. The need for large numbers of juvenile fish for stocking has stimulated the search for more efficient hatchery production. A Walleye hybrid (Walleye X Sauger _S. canadense_, commonly known as Saugeye) showed consistently better growth and survival than Walleyes in rearing ponds at the Senecaville National Fish Hatchery, Senecaville, Ohio (J. Hawkinson, Senecaville National Fish Hatchery, personal communication). In 1978, the survival and growth of juvenile hybrids stocked into Deer Creek Lake, Ohio was greater than that of Walleyes in most Ohio waters (R. Schaefer, Ohio Division of Wildlife, personal communication). Rapid growth and high survival of hybrids in both the hatchery and the reservoir suggested that hybrids might be more economical than Walleyes to raise for stocking. 
Literature on the biology of Walleye X Sauger hybrids is sparse. Natural hybrids occur rarely (Nelson and Walburg 1977; Billington et al. 1988) and were first identified in 1943 in Norris Reservoir, Tennessee, where their growth rate appeared to be intermediate between those of the parent species (Stroud 1948). Hybrids are fertile (Hearn 1986) and have been stocked successfully in Ohio ponds (Lynch et al. 1982) and in Cherokee Reservoir, Tennessee (Humphreys et al. 1987).
Before feasibility of stocking hybrids as an alternative to Walleyes can be assessed, more information is needed on the biology of hybrids, especially in comparison with Walleyes. Our objectives were to compare habitat preference, survival, growth, foods, and harvest of hybrids and Walleyes stocked in a reservoir.

*Study Area*​ The study was conducted from 1979 to 1982 in Pleasant Hill Reservoir, a eutrophic, 344 hectare reservoir in Northwestern Ohio. Maximum depth was 13m and mean depth was 5m. The reservoir was thermally stratified at a depth of 4-5m during June through early September. Temperatures in the epilimnion ranged from 20-24 degrees C. and the hypolimnion was anoxic. Midlake secchi disk transparencies usually ranged from 1 to 2 m but were lower (minimum, 0.36m) during flooding. Inshore transparencies were not measured regularly, but were generally lower than midlake readings and were directly related to substrate particle size. 
The Ohio Division of Wildlife has stocked Walleyes periodically in Pleasant Hill Reservoir since 1950. No natural reproductiuon of Walleyes has been documented since 1969. During 1976-1978, Walleyes of 44-75mm total length (TL) were stocked annually at a rate of about 35 fish/hectare. The reservoir also contains reproducing populations of Largemouth Bass _Micropterus _ _salmoides_, Smallmouth Bass _M. dolomieui_, White Bass _Morone __ chrysops_, White Crappie _Pomoxis annularis_, and a variety of nongame species, of which Gizzard Shad _Dorosoma cepedianum _ and Brook Silverside _Labidesthes sicculus_ are most numerous. Muskellunge _Esox masquinongy_ immigrate into the reservoir from a stocked population upstream.

* Methods​* Juvenile Walleyes and hybrids were stocked into Pleasant Hill Reservoir annually during late May or early June 1979-1982. Except in 1980, all fish were obtained from the Senecaville National Fish Hatchery, and both hybrids and Walleyes were stocked at a rate of 73 fish/hectare. In 1980, flooding delayed stocking by 1 week , during which time mortality at the hatchery was high. The surviving 17,000 Walleyes and 750 hybrids were supplemented with 10,000 hybrids from the London (Ohio) Fish Hatchery of the Ohio Division of Wildlife. The supplemental hybrids had been used in experiments with dry diets and were emaciated. In 1980, stocking rates were 49 Walleye and 31 hybrids per hectare.
Fish sampling.-Sampling began within 1 week after stocking and was conducted at least twice monthly through September. We used a bag seine (11m x 1.8m, with 5-mm-bar mesh) during the day in June and July and electrofishing (pulsed DC) at night from August through September. We categorized inshore habitats acccording to slope, wave exposure, and substrate. The open-water limnetic habitat was not sampled. To determine inshore habitat preferences, we sampled at least once each month at three to four standard stations in each habitat type. We used catch per unit effort (CPE) as a comparative measure of habitat preference. We could not use seines effectively for sampling exposed rock or steep rock areas; thus habitat preference analysis for June and July were were restricted to muck, clay-sand, and protected rock habitats. Because of delayed stockings in 1980, sample sizes of hybrids were small and these data were not included in in habitat analyses. Because there were only one or two samples per month, we combined data for 1979, 1981, and 1982 and tested for differences in habitat use (two-way analysis of variance, ANOVA) between age-0 hybrids and Walleyes within each month and between months (June and July or August and September) for each type of fish. Data were transformed as (X + 0.5)1/2 to normalize variance. 
We estimated population sizes of young-of-year hybrids and Walleyes in October of each year. Fish were captured at night by electrofishing and marked with a pelvic fin clip. In 1981 and 1982, we recaptured enough fish (>25) of both groups to enable us to use the Schnabel Formula (Ricker 1975). Recapture of Walleyes in 1979 and of hybrids in 1980 were too low to permit use of this formula. However, relatively precise estimates were obtained for the other group in each year. Because the ratio of age-0 Walleyes to hybrids was nearly constant on each night we sampled (four nights in 1979 and six nights in 1980), we based estimates of young-of-year Walleyes in 1979, and of hybrids in 1980, on their proportion in the total catch. A similar procedure was followed in 1980 for estimating hybrid numbers.
All captured hybrids and Walleyes were measured (TL) and weighed, except during for population estimates when a subsample of each group was weighed. We collected additional length and weight data from age-1 and older fish collected by electrofishing or fyke netting in April 1980-1983. Scale samples were taken from all fish longer than 350mm to determine age. Ages of fish less than 350mm were determined by length. 
Diet analysis.-Subsamples (maximun of 10/site.d) of age-0 hybrids and Walleyes were preserved in 10% formalin for stomach content analysis. Stomachs of older fish were preserved in formalin. Stomach contents were identified to species for fish and to family for invertebrates. We measured total length of intact fish taken from stomachs. Many Gizzard Shad were partially digested and impossible to measure, so we used a procedure similar to that of Knight et al. (1948) and measured either standard length (SL) or backbone length (BL). Total length was then estimated from equations derived from measurements of 180 preserved Gizzard Shad, 31-142mm TL.
Creel survey.-We conducted stratified, random creel surveys during April through September 1980-1982. Survey effort varied among years. In 1980, efort was 24 h/week and surveys were conducted on two weekdays and one weekend day (randomly selected), except in April and September when effort was 16 h/week and we surveyed on only one weekday. On each sampling day, the survey was conducted during a randomly selected 8-h period in either morning (0600-1400 hours) or evening (1400-2200 hours). A roving creel clerk counted all anglers on the lake every 2h. In 1981, effort was increased to 40 h/week and we surveyed on both weekend days. In 1982, effort was reduced to 30 h/week and was reapportioned to apply more effort during periods of highest variance. Thus a survey day was lengthened to 10 h and we again surveyed both weekend days.
Shore and boat anglers were interviewed between counts and all harvested game fish were measured. Hybrids and Walleyes less than 350mm were assigned to age classes based on length.Ages of larger fish were based on scales.
The tailwater pool below Pleasant Hill Dam is small (0.26 hectares) and subject to flooding, but does receive moderate fishing pressure under normal water conditions. In 1980 and 1982, tailwater surveys were integrated into the normal procedures for counts and interviews at the reservoir. In 1981, flooding prevented fishing in the tailwater for most of May and June; thus we did not survey the tailwater in that year.
In 1983, the Ohio Division of Wildlife conducted a creel survey on Pleasant Hill Reservoir from April through june (creel data from 1980 to 1982 showed that most Walleyes and hybrids were harvested during toose months). Effort was 20 h/week and included at least one weekend day. The tailwater was not surveyed. Count and interview procedures were similar to those in previous years, and scales were taken from all hybrids and Walleyes for age determinations.

* Results*​_Habitat Preference_

During June and July, hybrids and Walleyes were most frequently collected in inshore habitats with fine substrates. Habitat preferences did not differ between hybrids and Walleyes in June or July (P>0.2) but were significantly different in August and September (P<0.001), when hybrids were more common than Walleyes over fine substrates and Walleyes were taken mostly in exposed rock or steep rock habitats. There were no differences in habitat selection for either group between June and July (P>0.2) or between August and September (P>0.08).
Walleyes and hybrids may have inhabited exposed rock and steep rock habitats in June and July, when we could not sample these areas effectively. However, occasional electrofishing samples in these habitats in mid to late July and occasional seine hauls in exposed rock areas produced few stocked fish.
We did not capture enough yearling and older fish to analyze inshore habitat use, but electrofishing CPE suggested that both hybrids and Walleyes moved offshore during Summer. In July and August, CPE averaged about 0.3-0.05 times the CPE in Spring or Fall. There are many possiblee reasons for this movement (e.g., changing prey distribution), but, in Pleasant Hill Reservoir, offshore movement coresponded to the period when surface temperatures exceeded 22 degrees C. Field studies indicate that adult Walleyes prefer temperatures of 21-23 degrees C. (Hokanson 1977) and avoid temperatures of above 24 degrees C. (Fitz and Holbrook 1978). During midsummer in Pleasant Hill Reservoir, temperatures of 22-24 degrees C. (with at least 2mg/L dissolved oxygen) were available only at depths of 3-5 m, beyond the range that we could sample effectively by electrofishing.

_Survival_
Survival rates from stocking to October varied from 7 to 36% for hybrids and from 9 to 28% for Walleyes. Neither group had consistently better survival than the other; in 1981 and 1982, rates were similar between groups, but hybrids survived better in 1979 and Walleyes in 1980. Poor survival of hybdids in 1980 was probably due to their poor condition when stocked. Poor survival of Walleyes in 1979 may have been due to transport and stocking stress. We were not able to measure mortality at time of stocking, but many more Walleyes than hybrids were seen floating dead after release in 1979. In 1981 and 1982, stocking mortality appeared to be low for both groups of fish.
For each year class, ratios of age-0 hybrids to Walleyes in seine and electrofishing catches throughout Summer and Fall were similar to ratios in the Fall population estimates and in the harvest in subsequent years, except in the 1982 year class in the 1983 harvest. Persistence of these ratios in the harvest indicates that mortality rates were probably similar between the two groups after age 0. Differences in survival in 1979 and 1980 apparently developed by the end of June because ratios of hybrids to Walleyes in field samples remained constant after June.
Annual variations in survival of Walleyes and hybrids may also be related to differences in water discharge rates among years and loss of fish through the dam. Apparently, hybrids and Walleyes were lost through Pleasant Hill Dam at similar rates because survival rates were similar in 1981 and 1982, and ratios of hybrids to Walleyes for each year class were consistent over time. During our study, 1979 and 1982 were dry years and reservoir discharges were after stocking were low. In 1980 and 1981, heavy rains in late May and early June produced high discharges. However, in 1980, stocking was delayed until floodwaters had receded, thus newly stocked fish experienced relatively nlow discharges. If poor survival of Walleyes in 1979 and hybrids in 1980 was due to physiological stress, a negative correlation is indicated between survival and reservoir discharge rates after stocking for both Walleyes and hybrids.

_Growth_
Growth did not differ between age-0 hybrids and Walleyes, either within or among years (ANOVA;P>0.05). Fish in both groups completed annual growth by mid-October, when mean total length was 235mm and mean weight was 110g over all years. Mean lengths and weights did not differ between hybrids and Walleyes before age 2, when hybrids became consistently longer and heavier than Walleyes (P<0.05). By Fall 1982, the 1979 year class of hybrids averaged 555mm and 1,902g, and that of Walleyes averaged 519mm and 1,482g. We did not capture enough fish identifiable by sex to evaluate differences in growth between males and females.
The relation of length to weight was nearly identical for hybrids and Walleyes over all years. We developed length-weight regressions for both groups based on data combined for all years.

_Foods_
We examined stomachs from 1,305 hybrids and 789 Walleyes of all ages over all years. About 20% were empty. Invertebrates were eaten by both groups in all years but were an important part of the diet only for age1 and older fish in early Spring. Both hybrids and Walleyes were mainly piscivorous within 1 week after stocking. The most common fish eaten were Gizzard Shad. Hybrids had a slightly lower percentage occurrence of Gizzard Shad in their diets than did Walleyes in all years and also ate a wider variety of other fishes, most of which were littoral species. Predation by one stocked fish on another was noted only once, when an age-1 hybrid had an age-0 hybrid in its' stomach.
Lengths of forage fish in stomachs of stocked fish were similar among years; thus we pooled data for all prey species over all 4 years. For age-0 predators, we ran linear regressions of both mean and maximum lengths of forage fish eaten versus mean predator length, grouped by 25mm intervals. Mean and maximun total lengths of prey were directly related to predator total length. Regression slopes did not differ between hybrids and Walleye for either data set. For age-0 predators longer than 50mm, mean prey length was about 30% of predator length, which agrees with data from Cherokee Reservoir, Tennessee (Humphreys et al. 1987).
There was a discontinuity in the predator-prey length relations for age-0 and age-1 predators. Mean and maximum lengths of prey were lower for small age-1 predators (250-325mm) than for large age-0 predators, but for for predators longer than 325mm, values were similar to those of large age-0 fish. This discontinuity was due to the predominance of young-of-year Gizzard Shad in the diets of all age groups. In Fall age-0 hybrids and Walleyes averaged about 225mm and fed mainly on Gizzard Shad 50-90mm long. In Spring, at age 1, they fed on invertebrates before switching to young-of-year Gizzard Shad in early Summer. At that time, young-of-year Gizzard Shad averaged about 20-40mm. This produced a large decrease in mean and maximum prey lengths at predator lengths of 225-250mm, the length interval during which the transition occured from age-0 predators feeding on one year class of Gizzard Shad to age-1 predators feeding on the next year class of Gizzard Shad.

_Harvest_
Walleyes and hybrids in Pleasant Hill Reservoir showed similar seasonal and annual trends in vulnerability to angling. Angler success (harvest per 100 angler-hours) for all species was higher in 1980 and 1983 than in 1981 and 1982. Harvest rates for hybrids and Walleyes in the reservoir were about 1-3 fish/100 angler-hours in 1980 and 1983, but only 0.2-0.6 fish/a100angler-hours in 1981 and 1982. Most anglers did not distinguish between Walleyes and hybrids, but those who did found hybrids to be an acceptable alternative to Walleyes. From 1980 through 1982, 64-94% (mean,84%) of total harvest of both hybrids and Walleyes occured during April-June. Catch per unit effort for hybrids and Walleyes averaged 6.3 times higher during April-June than during July-September.
Harvest rates for both groups were higher for boat anglers than for shore anglers in all years except 1980. The discrepancy in 1980 may have resulted because nearly all Walleyes and hybrids harvested were yearlings, whiuch may spend more time inshore than do older fish. Most stocked fish were caught in the reservoir but, in 1980 and 1982, 6-33% of the total harvest for each group came from the tailwater. Harvest rates for hybrids were higher in the tailwater in 1980 but were similar in the tailwater and the reservoir in 1982. Most stocked fish taken in the tailwater were yearlings.

*Discussion*​ The life history and behavior of a hybrid fish might be expected to be intermediate between those of the parent species. Nelson (1968) found that Walleye x Sauger hybrids showed morphological characteristics intermediate between those of the parents but more closely resembled the female parent. In our study, the biology of hybrids was similar to that of the Walleye (female) parent, but hybrids also exhibited some of the characteristics associated with Saugers
Our data on inshore habitat use by age-0 Walleyes agree with most published information. Age-0 Walleyes prefer sand or gravel substrates (Johnson 1969), although in early Summer they can be found over muck (Johnson 1969) and sometimes over all bottom types, including silt and rubble (Raney and Lachner 1942). The preference for finer substrates shown by age-0 hybrids agrees with the preference of Saugers for more turbid habitat (Schlick 1978) and suggests that hybrids may be more sessitive to light than Walleyes. The offshore movement by older hybrids and Walleyes during Summer agrees with data for both Walleyes (Rawson 1957; Johnson 1969) and Saugers (Cady 1945) from other waters.
The diet of Walleyes in Pleasant Hill Reservoir was similar to that reported in the literature. In general, Walleyes are pisciverous after reaching 50-60mm if forage fish are available (Maloney and Johnson 1957; Priegel 1970). When available, Gizzard Shad are typically the most common forage item (Walburg et al.1971; Fitz and Holbrook 1978). In Pleasant Hill Reservoir, Gizzard Shad were found primarily offshore and in the upper portion of the water column. Although hybrids also ate mostly Gizzard Shad
they ate more of other forage fishes than did Walleyes, including many species commonly associated with the bottom; this is typical for Sauger (Swenson 1977). In Cherokee Reservoir, Tennessee,hybrids fed mostly on Dorosoma spp. but also ate some littoral species (Humphreys et al. 1987). Lynch et al. (1982) found that hybrids fed readily on centrarchids and cyprinids in shallow ponds with dense macrophytes, habitats where Walleyes typically do not do well.
Growth of Walleyes in Pleasant Hill Reservoir was faster than average Walleye growth in Ohio reservoirs but slower than in Norris Reservoir, Tennessee. Hybrid growth was faster than most Walleye, Sauger, or other hybrid growth in Ohio. Growth of Hybrids in other recently stocked Ohio reservoirs has also been faster than average Walleye growth in the state. Hybrid growth in Pleasant Hill Reservoir was similar to that of hybrids in Norris Reservoir through age-2, but older hybrids had higher mean lengths than any Walleye, Sauger, or hybrid in Norris Reservoir. The fastest growth recorded for hybrids was for the initial year class in Cherokee Reservoir, Tennessee, where fish averaged 305mm at age-1 (Humphreys et al. 1987).
The difference in growth between age-2 and older Walleyes and hybrids in Pleasant Hill Reservoir may have been due to (1) hybrids use of energy for somatic growth rather than for gonadal developement, (2) heterosis in hybrids, or (3) Protracted feeding by hybrids. Failure to develop gonads was probably not a major factor. Under controlled conditions Walleye x Sauger hybrids have matured (Hearn 1986;T. Nagel, Ohio Division of Wildlife, personal communication). we sampled several ripe male hybrids (age 2) in 1981 and two gravid females (age 3) in 1982. Mature and immature hybrids of the same age were similar in length and weight. Thus, some portion of the hybrid population in Pleasant Hill Reservoir did develop mature gonads, and at the same time as Walleyes.
Heterosis in hybrids may have increased growth rates, but this possibility was outside the scope of our study. Work on the genetics of hybrids and Walleyes is needed to answer this question.
Protracted feeding by hybrids appears to be the most likely cause of their faster growth. After age-1, Walleyes lost weight over Winter, while hybrids gained weight. Walleye and Sauger differ in Winter feeding activity; Saugers feed more than Walleyes and contain more visceral fat (Dendy 1946; Schlick 1978). If hybrids, like Saugers, feed more than Walleyes over Winter, that could account for their faster growth.
Neither Walleyes nor hybrids exhibited consistently better survival in Pleasant Hill Reservoir. For hybrids stocked into small ponds, Lynch et al. (1982) estimated first-Summer survival rates of 31 and 83% in two of four ponds and no survival in the remainin ponds. They attributed poor survival to predation. Physiological stress and reservoir discharge appeared to be important in determining survival rates during our study. Reservoir discharge may be coorelated with many factors that could effect fish survival (e.g., turbidity, temperature, food supply), but we feel that direct loss of fish through the dam was the most likely cause for reduced survival after high discharges. Losses of Walleyes and Saugers through dams have been documented in various waters; heaviest losses occured among juveniles during high discharges from late Winter through Spring (Groen and Schroeder 1978;Smith and Andersen1984; Jernejcic 1986). Large losses of Walleyes have resulted in reduced population sizes and year class strengths in impoundments (Groen and Schroeder 1978). 
Harvest rates of Walleyes in Pleasant Hill Reservoir was low compared to other Ohio impoundments. Harvest rate in the tailwaters was also low but similar to Dillon Lake Tailwater, which is considered one of the best Walleye tailwater fisheries in the state. Walleyes typically have not produced good tailwater fisheries in Ohio even after years of stocking. Hybrids harvest rate was low in Pleasant Hill Reservoir but typical of other systems where hybrids have recently been stocked. However, in all these systems, harvest rates for hybrids in the tailwater were higher than in the reservoir and were similar to rates for Walleyes in some of Ohio's better Walleye reservoirs. Apparenty hybrids are more likely than Walleyes to remain in tailwaters or to move into tailwater areas from downstream. These fishery characteristics are further indications that hybrids exhibit some Sauger-like behavior. Sauger fisheries are typically better in tailwaters than in reservoirs (Nelson and Walburg 1977). Saugers are more migratory than Walleyes (Collette et al. 1977). In Southeastern reservoirs, Saugers congregate below dams in Fall and remain there through Spring, whereas Walleyes congregate there only during the Spring spawning run (Hackney and Holbrook 1978). Thus, an extended Winter fishery is possible for Sauger but not for Walleye. In Ohio, hybrids are commonly taken in tailwaters in Winter (R. Schaefer, personal communication).

*Management Implications*​ Our data indicates that the biology of hybrids is intermediate between those of the parent species and that hybrids can be a reasonable alternative to Walleyes for stocking. The question remains, "What criteria should managers use in deciding whether to stock Walleyes or hybrids?" We feel that size and water retention time (reservoir volume divided by annual discharge) of impoundments may be useful in making that decision. Erickson and Stevenson (1972) related environmental features of Ohio impoundments to the success of Walleye stocking and concluded that large impoundments with clean gravel shoals and gradual water-level fluctuations were optimal; flood control reservoirs, which are characterized by large drawdowns, rapid water-level fluctuations, and variable discharges, had not maintained good Walleye populations because large numbers of Walleyes were apparently lost downstream. Willis and Stephen (1978) found that Walleye density and stocking success in Kansas reservoirs were directly related to retention time (low retention time indicates high discharge) and felt Walleye stocking was not justified in reservoirs with retention times less than one year. In Ohio, impoundments supporting the best Walleye harvests generally have high retention times-greater than about 0.7 year. There is a general relation between retention time and size of impoundment; thus, better Walleye reservoirs tend to be large, i.e., greater than about 1,000 hectares. High retention time does not guarantee good Walleye harvests, but no Ohio impoundment with a retention time of less than about 0.1 year has developed a good Walleye fishery(Ohio Division of Wildlife, personal communication), even after years of stocking. In contrast, excellent fisheries for hybrids now exist in tailwaters associated with impoundments of less than 500 hectares and retention times of less than 0.12 year. All of these impoundments (except Paint Creek Lake) had been previously stocked with Walleyes but never developed significant Walleye fisheries. These data indicate that, for large impoundments with retention times of about 1 year or more, stocking Walleyes is likely to be successful. For small impoundments with retention times of 0.1 year or less, stocking hybrids is more likely to produce a good fishery, particularly if anglers have access to tailwaters. More work is needed to determine the feasibility of stocking hybrids in impoundments with intermediate to high retention times.
A negative aspect of stocking hybrids is the possible dilution of gene pools in reproducing Walleye or Sauger populations. During this study we captured mature male and female hybrids. Male hybrids from Deer Creek Lake have been backcrossed with female Walleyes and the resulting eggs had about 10% hatching success (T. Nagel, personal communication). Hearn (1986) produced viable offspring from a cross of reciprocal hybrids and from backcrossing female reciprocal hybrids with male Saugers. Introgressive hybridization of Walleye and Sauger has been noted in natural populations (Billington et al. 1988). Where hybrids occur together with either parent species, they might interfere with reproduction of these fish or possibly spawn successfully with the parent species and introduce new genetic material into existing populations. More work is needed to determine the reproductive potential of hybrids in the field and the likelihood of backcrossings.
In conclusion, it appears that hybrids are a feasible alternative to Walleyes for stocking, particularly in impoundments with low retention times. However, before hybrids are stocked, consideration should be given to the possibility of genetic intermixing with existing populations of Walleyes or Saugers.


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## joel_fishes (Apr 26, 2004)

I had heard 9" after 1 year in the lake, 15" at the end of the second, then 18" after 3. I'm sure if you sent the ODNR an e-mail, they would answer you.

Joel


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## crawdiddy (Apr 10, 2006)

Hey Corey, I just saw you took the TIME to retype something with a bunch of fancy words. I am getting ready to read it now but just wanted to say thank you for doing that. Am sure I speak for many here too. good stuff I am SURE.

Now find that in fisherman article and get to werk   !


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## Playbuoy (Apr 6, 2005)

Corey,

Excellent information! It really answers a lot of questions I've asked myself a hundred times.


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## fishing_marshall (Jun 12, 2004)

Corey , thanks for posting that article. Good read.


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## acklac7 (May 31, 2004)

Corey said:


> acklac7, I took the time to retype the study for you.


 

Just got back in town...Dang Corey...Thanks!

As I suspected the P.Hill S-eye did grew a bit faster than the pond S-eye, but only by an inch or so. It would be neat to see if they grow faster in riveriene impoundments, Im betting they do . That article is extremely fascinating, im sure it took you a good chunk of time..Thanks a TON!

Also note the findings about stocking in relationship to high-water/spillway release, this probably helps explain the year-class & poor fishing issues as of late on the Scioto (although there are likely other factors). Be interesting to tag some small eyes and find out just how far they migrate.Maybe I can talk to my buddy @ OSU.

In regards to contacts @ OSU, I got a good one! One of my close buddy's just started a job working with OSU's fisheries division (possibly the OSU Div. of BioSciences?..I will double check). At any rate he is currently working on the Hoover S-eye project, and has access to all the information/data associated with it. I also believe he has access to all of OSU's S-eye info .
He said I could go tour the facility at anytime (it is conveniently located right behind my apartment). Evidently they got all sorts of S-eye related studies going on. One of them involves 3 sets of S-eye in different tanks, each tank has a different water clarity value. They set baitfish loose in the tank and observe how long it takes the baby-eye's to get them. Neat stuff!

Ill update this thread when I find out more about what info I can get my hands on. Im hoping I can get access to the mother-load


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## crawdiddy (Apr 10, 2006)

if anyone has a back collection of in fishermans. about 2-3 years ago there was an excellent article on river eyes.....even wiht a pic of the oshay dam.....and it talked about growth rates too,etc.


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