Despite clear positive effects on biodiversity and abundance, questions surround whether or not MPAs are effective tools in terms of fishery management, and the degree to which they provide measurable benefit in addition to other fisheries management strategies. The science, however, seems to provide clear answers: MPAs can benefit fishery yield when they protect older, larger fish allowing them to flourish as the broodstocks of highly productive spawners that help repopulate fished areas. Not only do MPAs increase the numerical density and biomass of target species, they also improve species richness which can restore larger ecosystem functioning, and in turn revive ecosystem services including carbon sequestration and water purification.
Despite their importance in preserving biodiversity and ecosystem services, MPAs have long faced criticism as “paper-parks”, where the good intention of protection is not backed by enforcement. Poaching often occurs at night or in the early morning which presents unique challenges for the limited enforcement officers who already struggle to patrol the dispersed MPAs during daylight hours. Consequently, small fishing vessels roam freely with little monitoring, and small boats can easily slip across reserve boundaries with little threat of consequence. As competition heightens between fishers along coastal zones, incentives to cross into MPA boundaries are increasingly enticing.
Novel technology, born out of a collaboration between Resource Legacy Fund, ProtectedSeas and California Marine Sanctuary Foundation, known as Marine Monitors (M2) enables protection of vulnerable MPAs from illegal activity. The M2 system utilizes shore-based radar systems with a high definition camera to monitor vessel track lines. Because vessels under 24 feet are not required to transmit Automatic Identification Systems (AIS), a tracking system required for larger vessels, there is a gap in ability to enforce small vessels. This is where the M2 program can help by monitoring small vessel activity around the clock. Boats moving below a certain speed within the MPA boundaries trigger the system and alert data managers to suspicious activity. This allows California Department of Fish and Wildlife, Coast Guard, and National Park Service enforcement officers to gauge compliance and even begin to understand patterns that haven’t been addressed before–like night fishing.
Comprehensive maps and reports allow enforcement officers to focus their effort on regions vulnerable to poaching and understand how to better manage MPAs. The M2 system has shown that many MPAs have high levels of compliance, where high concentrations of track lines along the edge of the MPA illustrate that fishers not only understand boundary lines, but also suggest another benefit of MPAs – “spillover” . Spillover has often been denied by some fishers, who debate the concept that healthy fish populations within the MPA boundaries overflow and bolster populations outside of the MPA zones, increasing catch.
The importance of novel technology used to remotely monitor marine environments expands far beyond the improvements to enforcement. Researchers at UCSB are using vessel track line data from M2 to better understand how to design MPAs for benefit to ecosystems and fisheries. One experiment looks to explore how protecting benthic habitat within MPAs for important commercial species, like lobster, might significantly improve catch outside protected areas.
Efforts to improve our understanding of how MPAs benefit the resilience of marine ecosystems will enable better design of these critical zones. It is important that our marine protected areas stay protected – and new projects like M2 can make that a reality by enabling reliable monitoring to improve compliance. Even more significant is the opportunity to communicate the overarching value of California’s advanced MPA system; conservation can work in tandem with human use for economic and ecological gain.
Works Cited
Marine Conservation Institute. Marine Protection Atlas: Global Marine Fishing Protection. (2021) Retrieved from: https://mpatlas.org/zones/
Davidson, L., Dulvy, N. Global marine protected areas to prevent extinctions. Nat Ecol Evol 1, 0040 (2017). https://doi.org/10.1038/s41559-016-0040
Text – S.Res.372 – 116th Congress (2019-2020): A resolution expressing the sense of the Senate that the Federal Government should establish a national goal of conserving at least 30 percent of the land and ocean of the United States by 2030. (2019, October 22) Retrieved from: https://www.congress.gov/bill/116th-congress/senate-resolution/372/text
Edgar GJ, Ward TJ, Stuart‐Smith RD. Rapid declines across Australian fishery stocks indicate global sustainability targets will not be achieved without an expanded network of ‘no‐fishing’ reserves. Aquatic Conserv: Mar Freshw Ecosyst. 2018; 28:1337–1350. Retrieved from: https://onlinelibrary.wiley.com/doi/pdf/10.1002/aqc.2934
Hameed SO, Cornick LA, Devillers R and Morgan LE (2017) Incentivizing More Effective Marine Protected Areas with the Global Ocean Refuge System (GLORES). Front. Mar. Sci. 4:208. doi: 10.3389/fmars.2017.00208 Retrieved from: https://www.frontiersin.org/articles/10.3389/fmars.2017.00208/full
Halpern, B., Lester, S., & Kellner, J. (2009). Spillover from marine reserves and the replenishment of fished stocks. Environmental Conservation, 36(4), 268-276. doi: 10.1017/S0376892910000032
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