Willard Perch...DWR Response

[PBH]

I like this a lot.  What else can we do more of, to prevent stunting in lakes like PV?

There is only 1 way to prevent a fish population from stunting:  limit population size.

The question then becomes:  how do you limit population size?

The answer to this lies within the 4 management tools available to fisheries managers:
1.  Fishing rules and regulations
2.  public relations and education
3.  fish stocking and fish removal
4.  habitat improvement and manipulation

Every lake and fishery is different, so the tools used may vary by the specific situation.

With Willard, fisheries managers have to first identify what is currently limiting the perch size.  Is it "stunting" (ie:  fish reaching sexual maturity at smaller sizes -- or, rather, slow fish growth)?  Or is it overharvest (ie:  fish being removed prior to reaching sexual maturity - or, rather, fish being removed at a young age).  Fish growth is the key.  You want fish populations to experience fast growth.  Fast growth occurs when population sizes are at the correct level.  Big fish are the result of fast growth -- not old age.

If the problem is stunting (slow growth) -- then adjusting regulations (#1) to restrict the amount of harvest (#3) would be counter productive and exacerbate the problem.  To the contrary, education (#2) should be employed along with regulations (#1) and higher limits (#3) should be implemented to remove more fish.

If the problem is overharvest by anglers (or even by birds or other predator animals!) -- then adjusting regulations (#1), educating the angler base (#2), and decreasing harvest limits (#3) should be implemented. 

Habitat improvement and manipulation (#4) is one of the more difficult tools to use, but is very important.  Most often we see this with stream habitat improvements and spawning area improvements to increase  natural reproduction - like Chris mentioned in his response, the DWR has done some habitat improvement in both shallow and deep water in places like Pineview.  However, this can also go the other way -- consider a reservoir with a dropping water lever after a fish spawn which leaves eggs high and dry.