Data from: Climate drives the geography of marine consumption by changing predator communities
Whalen, Matthew; Whippo, Ross; Duffy, Emmett (2020), Data from: Climate drives the geography of marine consumption by changing predator communities, Dryad, Dataset, https://doi.org/10.5061/dryad.8cz8w9gnm
The global distribution of primary production and consumption by humans (fisheries) is well-documented, but we have no map linking the central ecological process of consumption within food webs to temperature and other ecological drivers. Using standardized assays that span 105° of latitude on four continents, we show that rates of bait consumption by generalist predators in shallow marine ecosystems are tightly linked to both temperature and the composition of consumer assemblages. Unexpectedly, rates of consumption peaked at midlatitudes (25 to 35°) in both Northern and Southern Hemispheres across both seagrass and unvegetated sediment habitats. This pattern contrasts with terrestrial systems, where biotic interactions reportedly weaken away from the equator, but it parallels an emerging pattern of a subtropical peak in marine biodiversity. The higher consumption at midlatitudes was closely related to the type of consumers present, which explained rates of consumption better than consumer density, biomass, species diversity, or habitat. Indeed, the apparent effect of temperature on consumption was mostly driven by temperature-associated turnover in consumer community composition. Our findings reinforce the key influence of climate warming on altered species composition and highlight its implications for the functioning of Earth’s ecosystems.
The core data for this project consist of 1) results of marine consumption assays in which small pieces of squid were tethered to stacks (squidpops) and placed inside and outside of shallow seagrass meadows, 3) water tempearture records collected at the time of the assays, 2) counts from surveys of consumers (fish and large invertebrates) using hand-pulled seines, and 3) summaries of surveys of consumers and their interactions with squidpops collected using underwater videography. These core data are included in their rawest form. Various data summaries produced in R are also included. See Usage Notes below about location of R scripts.
Data for several explanatory variables were accessed from sources external to the project and the core dataset. The pieces of data used in the project are included in this dataset and they can be summarized as follows:
- environmental variables from Bio-ORACLE
- human population densities from the Gridded Population of the World
- fishing pressure data from the Sea Around Us project
- taxonomy and species traits from FishBase and the Reef Life Survey
In addition to raw data and pre-processed external data, we include a compilation of data from multiple sources that were used in statstical modeling analysis for the paper.
More information on individual data files and their contents, please see the accompanying README.txt file.
This dataset contains the core and supporting data for the MarineGEO Bitemap project (https://bitemap.wordpress.com), which seeks to map and understand the global distribution of consumption pressure in coastal marine ecosystems. This dataset contains core data about field feeding assays using tethered dried squid and surveys of predator communities. We include additional data about sites and about the organisms the live in the shallow seagrass and unvegetated habitats we surveyed.
There are a series of R scripts that are used to process and analyze the dataset. These scripts are available at https://doi.org/10.5281/zenodo.3998836.