El Niño underwater: monitoring the impact on Mexican kelp forests

Kelp forests are among the most productive marine ecosystems, supporting biodiversity and coastal livelihoods. However, extreme ocean warming events are threatening the species and communities that depend on them.

Since 2011 our collaborative team has been monitoring 15 kelp forest sites along the Baja California Peninsula, Mexico, and since 2022 MasKelp expanded this effort to 40 sites in collaboration with local Universities, NGOs and fishing cooperatives. In August 2026, we completed our annual surveys across all 40 sites. Just two weeks later, fishing communities began reporting unusually warm waters and widespread die-offs of kelp and invertebrates. In response, our team rapidly revisited three sites, documenting dramatic ecological changes, including the loss of sea urchins from surveyed areas.

Supported by the 2027 Deconstructed El Niño Satellite Projects, MasKelp will revisit eight established monitoring sites to document ecological changes associated with the developing El Niño event. Using standardized underwater surveys, we will compare the abundance and diversity of fish, invertebrates and algae with data collected before the warming event and in previous years.

Working alongside local fishing cooperatives and the Instituto de Investigaciones Oceanológicas from the Universidad Autónoma de Baja California, this expedition will provide a rare opportunity to document ecological transformations as they unfold. The findings will strengthen long-term monitoring, help assess ecosystem persistence and recovery and support coastal communities in understanding and responding to climate-driven changes in their kelp forests.