Factors Associated with Increased Walleye Production in Lined Compared to Earthen-Substrate Ponds

• 作者: Matthew J. Ward Brian G. Blackwell
• 来源期刊: 动物科学期刊(英文)
• 学科: 经济
• 关键词: WALLEYE Fingerling Culture Pond-Substrate Type
• 年，卷（期）: 2021,（1）
• 页码范围: 50-61
• 页数: 12页
• 分类号: F42

摘要

Walleye (<i><i><span style="font-family:Verdana;">Sander vitreus</span></i><span style="font-family:Verdana;"></span></i><span style="font-family:Verdana;">) fingerling production can be enhanced when the pond substrate is altered from earthen soils to an exposed liner;however, few differences in water chemistry, prey densities, and food habits have been identified that could potentially explain this production difference. Lack of an explanation led to further comparison of walleye fingerling culture between substrate types during 2016. Two ponds of each type were stocked with 1</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> to 3-day</span><span style="font-family:Verdana;">-</span><span style="font-family:;" "=""><span style="font-family:Verdana;">old walleye fry, but lined ponds received an additional 104,166 fry/ha and were stocked 1 or 2 days later than earthen ponds (May 10). Walleyes in lined ponds achieved a growth advantage on May 31 (+2.5 mm) and on June 6 (+3.3 mm), but lengths were not significantly different at harvest (June 15). Lined ponds increased walleye yield and number 1.8-fold while not reducing </span><span style="font-family:Verdana;">individual fish size at harvest compared to earthen ponds. Walleye food habits were generally similar between pond types with a greater </span></span><span style="font-family:Verdana;">number</span><span style="font-family:Verdana;"> of</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> zooplankton being consumed through June 6 followed by an increase in larval chironomid consumption at harvest (June 15). After May 30, lined ponds exhibited lower dissolved oxygen and higher ammonia-nitrogen concentrations even though earthen ponds received additional (157 kg/ha) alfalfa (<i></i></span><i><i><span style="font-family:Verdana;">Medicago sativa</span></i><span style="font-family:Verdana;"></span></i></span><span style="font-family:Verdana;">) meal fertilizer. Also, at this time pH declined abruptly and r