On the fish tail of Mother’s Day weekend, we wanted to devote this week’s post to all the fish mothers out there. While mama fish may not have the same maternal instincts of our own dear mums, they do their part to sustain fish populations, particularly BOFFFFs. “What is a BOFFFF?” might you ask…A Big Old Fat Fecund Female Fish.
The BOFFFF Hypothesis postulates that preserving the older age classes can be particularly important to fisheries management, specifically the recovery of overfished stocks. Older, larger females (aka BOFFFFs) often produce more eggs and larger eggs that survive better than those from younger females, which equates to a greater contribution to the population. So, by this rationale, protecting BOFFFFs from harvest can help sustain populations and help overfished populations recover more quickly.
The BOFFFF Hypothesis was originally developed to assist with Pacific rockfish recovery, but the theory extends to many other long-lived species. This thinking is a shift from more traditional forms of fisheries management which seek to focus protective measures on the smaller, younger fish (usually with size-selective gear) so that they can grow to reach reproductive age.
But sustainable fisheries management is more nuanced than just protecting young fish or protecting old fish. Protecting both is often necessary. Management strategies, such as slot limits, where fisherman can harvest fish only within a specific size range, can help support populations from both ends of the age structure, leaving the young fish to reach reproductive maturity and the BOFFFFs to supply an abundance of larger, stronger eggs.
For more information on the BOFFFF Hypothesis:
Berkeley S. A., Hixon M. A., Larson R. J., Love M. S. Fisheries sustainability via protection of age structure and spatial distribution of fish populations, Fisheries, 2004; 29:23-32.
Berkeley S. A. Pacific rockfish management: are we circling the wagons around the wrong paradigm?, Bulletin of Marine Science, 2006; 78:655-668.
Hixon, M. A., Johnson, D. W., Sogard, S. M. BOFFFFs: on the importance of conserving old-growth age structure in fishery populations. ICES Journal of Marine Science, 2014; 71 (8): 2171-2185.
Longhurst A. Murphy’s law revisited: longevity as a factor in recruitment to fish populations, Fisheries Research, 2002; 56:125-131.
From the Fisheries Blog out to all mothers, including BOFFFFs, thank you for all that you do!