Jon Witman, Franz Smith, Fiona Beltram and Alejandro Perez Matus arrived in July 2016 for another productive summer of subtidal research. Their objective was to continue their NSF sponsored investigation of the impacts of the current strong El Nino on the benthos and reef fish assemblages in the central Galapagos Islands. Over a period of 7 weeks they conducted video and photo surveys of monitored coral transects, photographed permanent quadrats at 6 and 15 m depth, performed band transects for mobile invertebrates and fish, deployed “fish cams” to census fish in the absence of divers, changed temperature loggers, deployed barnacle recruitment plates, profiled the water column with a CTD, studied the impact of noxious cyanobacteria and re-surveyed sites where a novel white skin disease broke out during the height of El Nino in January 2016. Phew.
So far only a few corals have bleached. The abundance of sponges remained low after the mortality event during peak El Nino conditions. We observed some recruitment of Pocilloporid corals suggesting that finger corals may be able to rebound slightly from high mortality during past El Nino’s. The ecosystem is transitioning to a La Nina which should bring high recruitment of barnacles which are major prey items in the Galapagos subtodal food web.
We missed working with PhD candidate Robbie Lamb, who was out of the water temporarily with a knee injury. Dr. Alejandro Perez Matus prevented a data gap in Robbie’s study of El Nino impacts on fish assemblages by travelling up from Santiago, Chile to do the band transects for fish. Thank you Ale!
One of the perks of working in the Galapagos is frequent encounters with some of the ocean's biggest and most charismatic large vertebrates. Here Jon and Franz exit the water accompanied by dolphins after a dive off of Pinzon Island (video: A. Perez-Matus).
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