Examining the diversity, stability and functioning of marine fish communities across a latitudinal gradient

Aim: As anthropogenic stressors on the biosphere intensify, understanding
how communities respond to disturbances is critical. Biodiversity is often
thought to promote the stability of communities over time and enhance
ecosystem functioning. However, results have been inconsistent, and the
multifaceted linkages among diversity, stability, and functioning under
acute disturbances remain poorly understood. We experimentally tested the
responses of marine fish communities to disturbance (i.e., acute habitat
loss) across a diversity gradient spanning 35º degrees of latitude in the
western Atlantic Ocean to assess the diversity-stability relationship and
the interplay between diversity, stability, and fish biomass recovery (as
a proxy for function) in marine fish communities. Location: Western
Atlantic Ocean (Maine, Massachusetts, North Carolina, Florida [USA],
Belize, and Panama). Time period: 2016 – 2017 Major taxa studied: Small,
bottom-dwelling (‘cryptobenthic’) fishes Results: Diversity showed a
negative effect on community stability at both the regional (across docks)
and local (within docks) scales. Similarly, local diversity was negatively
correlated with ecosystem function. These effects are exacerbated by the
habitat loss imposed via our experimental treatment. Main conclusions: Our
results suggest that habitat loss may more intensively re-shuffle diverse,
tropical communities, which impacts biomass recovery, our proxy of
functioning. Contrary to ecological theory, in small-bodied,
benthos-associated vertebrate communities, biodiversity may neither
promote stability nor functioning, suggesting that human disturbances may
be particularly impactful in tropical, high-diversity ecosystems.