New Jersey Division of Fish and Wildlife Back to State of NJ Homepage Back to Fish and Wildlife Homepage Back to NJ DEP Homepage

Hackettstown Hatchery Brood Stock Collection is Underway! (Part I)

by Craig Lemon
Hatchery Superintendent

Winter is holding on this year, but brood stock collection is going strong. The crew at the Hackettstown Hatchery is out braving the cold, snowy and windy days that nature has thrown at northwest New Jersey in March and early to mid-April this year (2003).

The hatchery begins broodstock operations each season when the ice melts from Budd Lake, located just a few miles from the hatchery on Route 46. Three "Pennsylvania style" trap nets were set into Budd Lake on March 26 this year compared to March 6 in 2002.

These nets were checked the following day and yielded 103 northern pike, hundreds of yellow and white perch and dozens of fish from 10 other species. Budd Lake is being used as the hatchery's brood stock lake for northern pike. (The hatchery has also used Spruce Run Reservoir and Farrington Lake for northern pike in the past.)

The Budd Lake nets were checked five times from March 27 - April 4. They were pulled from the lake on April 4 after capturing 184 northern pike. Of the 184 northerns captured, 49 were females and 135 were males. Twenty-one of the females were spawned by hatchery staff yielding 654,299 eggs. The females averaged 31,157 eggs per fish, which is close to the 35,000 per fish average from 2002.

Ed Conley with pike
Ed Conley strips eggs from a Northern Pike

The hatchery collected more fish this spring from Budd Lake in 10 days of netting than it did in 16 days of netting the same locations in 2002. A quick comparison of fish lengths shows very little change from last year. This year's males averaged 21.7 inches compared to 22.1 last year, while this year's females averaged 26.4 compared to 26.5 from last year.

All of the fish used for egg collection have been safely returned to Budd Lake. The spawning run was shortened to only a few days this year because of the late ice out. Many of the females came into the hatchery already spawned out. Northern pike eggs take ten days to hatch and the resulting fry will grow to 7 inches at the hatchery and be stocked in late June and early July. The waters stocked with northern pike include Cranberry Lake, Pompton Lake, Spruce Run Reservoir, Pompton River, Budd Lake, Farrington Lake, Millstone River and Passaic River.

Stripping walleye eggs and milt
Ed Conley and Amy Schweitzer strip walleye

The second brood fish the Hackettstown crew searches for is the walleye. Two trap nets, one "Pennsylvania style" and one "South Dakota style", were set in Swartswood Lake (Sussex County) on March 31. The netting crew checked these nets the following morning and collected 70 adult walleye for spawning. Hatchery personnel stripped just under 1,000,000 eggs from 13 ripe female fish that afternoon.

As a result of lake temperatures hovering around 38 degrees this year, the number of walleye caught was significantly lower than last year - normal lake temperatures for this period of April are typically 42 - 46 degrees. Nets were checked 7 times from March 31 - April 11, yielding a total of 183 walleyes for spawning. This compares to a total of 303 fish that were captured in 2002 during an 11 day period.

Of the 183 walleye captured, 102 were females and the crew spawned 78 of them producing about 5.5 million eggs. The 78 females averaged 70,000 eggs each, 3.65 pounds and 20.2 inches. The males averaged 2.07 pounds and 17.6 inches. All of the fish were returned to the lake in good health.

Walleye eggs take 13 days to hatch, and hatching percentages range from 40 to 70 percent. The first million fry to hatch are placed into hatchery ponds after spending their first two days in hatchery tanks. The ponds are fertilized a week before the fry are introduced. This allows for a good plankton population to become established for these tiny fry to begin feeding on. The walleye fry become 2-inch fingerlings in 40 days if Mother Nature cooperates and allows the sun to shine and warm up the pond water.

In 2002, 300,000 of these 2-inch walleye were stocked into Greenwood Lake, Lake Hopatcong and the Delaware River. The hatchery keeps 80,000 of the 2-inch fingerlings and sets up 6 smaller ponds and grows them to 4 inches on fathead minnows. The 4-inch walleye are stocked in Monksville Reservoir, Swartswood Lake, Canistear Reservoir, Greenwood Lake and Lake Hopatcong.


Trap nets were placed into Monksville Reservoir and Greenwood Lake on April 14. The target species in these two lakes are walleye and muskellunge. Last year the nets produced a combined total of 147 walleye and 12 muskies.

The final two lakes to be netted are Echo and Mountain and the target species for these lakes is muskellunge. Echo Lake was not netted last year due to low water levels caused by the severe drought conditions. Higher water levels should produce a good netting season this year on these four lakes.

Stripping muskellunge
Ed Washuta and Ed Conley strip a muskellunge

Stay tuned to the Division of Fish and Wildlife's web site for a final summary of the 2003 brood stock collecting season, and see "Part II" for updated information.

Back to Fish and Wildlife Homepage Back to NJ State Homepage Back to NJ DEP Homepage