Skip to contents

Retrieve Trophic Level and Standard Error from FishBase

find_tl.Rd

This function retrieves the trophic level and its standard error for a given species from FishBase. It fetches data from the FishBase website, extracts the trophic level information, and formats it into a data frame.

Usage

find_tl(sp, mirror = "us")

Arguments

sp

A character string representing the species name. The species name should be provided as it appears on FishBase, but spaces will be replaced with hyphens.

mirror

A character string specifying the FishBase mirror site to use. Defaults to "us" (FishBase USA). Other mirrors can be specified if needed.

Value

A data frame containing the trophic level information for the species. The data frame includes the following columns:

  • species: The species name.

  • trophic_level: The trophic level of the species.

  • se: The standard error of the trophic level.

  • metric: The source used (if provided) e.g. "based on food items".

If there is no internet connection, or if the species page cannot be retrieved or parsed, the function returns NULL.

Examples

# Retrieve trophic level and standard error for a species
tl_info <- find_tl("Lutjanus campechanus")
#> Warning: cannot open URL 'https://www.fishbase.us/summary/Lutjanus-campechanus.html': HTTP status was '520 Unknown Error'
#> Error in file(con, "r"): cannot open the connection to 'https://www.fishbase.us/summary/Lutjanus-campechanus.html'
print(tl_info)
#> Error: object 'tl_info' not found