摘要：We observed cannibalism by juvenile and adult largemouth bass
(Micropterus salmoides) on their young-of-year (YOY) over nearly
three decades (1984–2012) in a small temperate lake located in
the Upper Peninsula of Michigan, USA. Largemouth bass are consistently
the only fish species in the lake, necessitating the
importance of studying filial cannibalism as a valuable energy
source although it has potential consequences on recruitment
and overall population structure. Annual whole-lake population
estimates of juvenile and adult bass ranged 91–460 individuals,
and these oscillations had significant differences between periods
of higher and lower densities. Captured bass >150 mm in total
length were individually tagged and had their stomach contents
analyzed before being released. Despite significant differences in
population estimates, we found no relationship with cannibalism.
Additionally, we found no apparent patterns relating cannibalism
to day of year, water temperature, or recruitment rates. We also
found no differences in cannibalism or the size of consumed YOY
between juvenile and adult bass. However, we found that recaptured
individuals who consumed YOY bass on two or more occasions
had significantly longer total length than individuals who
consumed YOY bass one time or not at all, which provides additional
evidence of dietary specialization as previously found in
this population. Notwithstanding these patterns in cannibalism
and the potential energetic benefits that it provides, we could
not discern the effects of it on either individual growth rates or
consequential changes in recruitment and overall population size.
Regardless of the ever-present pressure of filial cannibalism, the
population sustained recruitment across the whole study period.
