title: Tambora and the mackerel year: Phenology and fisheries during an extreme climate event.
abstract: Global warming has increased the frequency of extreme climate events, yet responses of biological and human communities are poorly understood, particularly for aquatic ecosystems and fisheries. Retrospective analysis of known outcomes may provide insights into the nature of adaptations and trajectory of subsequent conditions. We consider the 1815 eruption of the Indonesian volcano Tambora and its impact on Gulf of Maine (GoM) coastal and riparian fisheries in 1816. Applying complex adaptive systems theory with historical methods, we analyzed fish export data and contemporary climate records to disclose human and piscine responses to Tambora's extreme weather at different spatial and temporal scales while also considering sociopolitical influences. Results identified a tipping point in GoM fisheries induced by concatenating social and biological responses to extreme weather. Abnormal daily temperatures selectively affected targeted fish species-alewives, shad, herring, and mackerel-according to their migration and spawning phenologies and temperature tolerances. First to arrive, alewives suffered the worst. Crop failure and incipient famine intensified fishing pressure, especially in heavily settled regions where dams already compromised watersheds. Insufficient alewife runs led fishers to target mackerel, the next species appearing in abundance along the coast; thus, 1816 became the "mackerel year." Critically, the shift from riparian to marine fisheries persisted and expanded after temperatures moderated and alewives recovered. We conclude that contingent human adaptations to extraordinary weather permanently altered this complex system. Understanding how adaptive responses to extreme events can trigger unintended consequences may advance long-term planning for resilience in an uncertain future.
authors.affiliation: Department of Environmental Conservation, University of Massachusetts Amherst, Amherst, MA 01003-9285, USA.
authors.forename: Karen E
authors.initials: KE
authors.lastname: Alexander
authors.affiliation: Independent Researcher based in Maine.
authors.forename: William B
authors.initials: WB
authors.lastname: Leavenworth
authors.affiliation: University of Southern Maine, Portland, ME 04103, USA.
authors.forename: Theodore V
authors.identifier: 0000-0002-7096-2876
authors.initials: TV
authors.lastname: Willis
authors.affiliation: Alan Alda Center for Communicating Science, Stony Brook University, Stony Brook, NY 11794, USA.
authors.forename: Carolyn
authors.initials: C
authors.lastname: Hall
authors.affiliation: Department of Environmental Conservation, University of Massachusetts Amherst, Amherst, MA 01003-9285, USA.
authors.forename: Steven
authors.initials: S
authors.lastname: Mattocks
authors.affiliation: Department of Environmental Conservation, University of Massachusetts Amherst, Amherst, MA 01003-9285, USA.
authors.forename: Steven M
authors.initials: SM
authors.lastname: Bittner
authors.affiliation: Southwest Fisheries Science Center, La Jolla, CA 92037, USA.; Farallon Institute, Petaluma, CA 94952, USA.
authors.forename: Emily
authors.identifier: 0000-0001-9514-7344
authors.initials: E
authors.lastname: Klein
authors.affiliation: Department of Environmental Conservation, University of Massachusetts Amherst, Amherst, MA 01003-9285, USA.; Department of the Interior Northeast Climate Science Center, Amherst, MA 01003-9297, USA.
authors.forename: Michelle
authors.initials: M
authors.lastname: Staudinger
authors.affiliation: Department of the Interior Northeast Climate Science Center, Amherst, MA 01003-9297, USA.
authors.forename: Alexander
authors.initials: A
authors.lastname: Bryan
authors.affiliation: Department of Environmental Conservation, University of Massachusetts Amherst, Amherst, MA 01003-9285, USA.
authors.forename: Julianne
authors.initials: J
authors.lastname: Rosset
authors.affiliation: Marine Program, Boston University, Boston, MA 02215, USA.
authors.forename: Benjamin H
authors.identifier: 0000-0002-6206-4638
authors.initials: BH
authors.lastname: Carr
authors.affiliation: Department of Environmental Conservation, University of Massachusetts Amherst, Amherst, MA 01003-9285, USA.
authors.forename: Adrian
authors.identifier: 0000-0001-9510-8011
authors.initials: A
authors.lastname: Jordaan
mesh_terms: D000818:Animals; D057231:Climate Change / Q000266:history*; D005398:Fisheries / Q000266:history*; D049672:History, 19th Century; D008281:Maine; D010473:Perciformes
keywords: Complex Adaptive Systems; Gulf of Maine fisheries; Historical ecology; Tambora; anadromous; coupled human and natural systems; extreme climate event; food security; pelagic; phenology