Data for: Ecological interactions mediate projected loss of kelp biomass under climate change

This dataset contains the data used to define a stacked species distribution model (SDM) for kelp (Ecklonia radiata) and urchins (Centrostephanus rodgersii) in eastern Australia. The spatial extent of this study encompasses the eastern coast of Australia, between 28.0–37.5°S. Within this region, E. radiata is the only laminarian kelp species, while C. rodgersii is the dominant urchin species, with ecological interactions between these two species creating a patchwork of kelp forests and urchin barrens on shallow reefs., Modelling of kelp and urchin distributions was conducted using a stacked-SDM which consists of two sub models; a kelp SDM and an urchin SDM, that are integrated to ultimately estimate the distribution of kelp biomass throughout the study extent. The stacked-SDM was constructed using kelp percentage cover data and data on relative densities of the urchin C. rodgersii, from randomly positioned 200 m transects at 23 sites spread along the eastern Australian coastline (see data). The kelp SDM was developed by matching kelp percentage cover data (binomial response variable) to a suite of satellite-derived environmental data of likely importance to kelp persistence and data on relative urchin densities. Explanatory variables for the kelp SDM were selected by trialling explanatory variable combinations in a generalised additive mixed effects modelling (GAMM) framework, with the most parsimonious kelp SDM (optimal model) selected using the Akaike information criteria (AIC). The optimal model pr..., The spreadsheet containing the data has the following columns.

Site = Unique site name
Transect = Transect number at site
Name = Unique transect name
Sample  = sample number on transect
Latitude = Latitude of sample in decimal degrees
Longitude = Longitude of sample in decimal degrees
Depth = Average depth of sample (m)     
Kelp pts = Number of random points in sample images overlaid on kelp (out of 50)
Kelp cover = Kelp cover for sample (%)
Urchin density = Urchin density in sample (Urchins/m2)               
PARaz = Average photosynthetically available radiation (PAR) at the seabed at the sample location (Einstein.m-2.d-1)             
Temperature (Tmx) = Summer maximum temperatures at the seabed (Deg. C)