yftdiet: Yellowfin Tuna Diet data

In pkuhnert/diet: Performs an analysis of diet data using univariate trees

Yellowfin Tuna Diet data

Description

Yellowfin tuna (YFT) were captured by purse-seine fishing vessels in the eastern tropical Pacific (ETP) between 16 August 2003 and 16 November 2005.

Usage

yftdiet

Format

A data frame with 660 observations on the following 13 variables.

TripSetNo

A unique number representing the purse-seine vessel's Trip and Set number

TripSetPredNo

A unique number representing the purse-seine vessel's Trip and Set number, and the YFT sample number

Date

Date YFT was captured

Quarter

Quarter in which YFT was captured

Year

Year in which YFT was captured

Lat

Latitude coordinates where YFT was captured

Lon

Longitude coordinates where YFT was captured

SST

Sea-surface temperature at location where YFT was captured, measured in degrees C

PredSpp

Predator species

Length

Predator length in mm

Fullness

Visual estimate of YFT stomach fullness, expressed as a percentage

W

Case weights

Group

Prey Group. A factor with levels Argonautidae Exocoetidae Galatheidae Hemiramphidae Myctophidae Nomeidae Ommastrephidae Ostraciidae Phosichthyidae Portunidae Scombridae Tetraodontidae

Details

YFT were sampled onboard the vessels by observers of the Inter-American Tropical Tuna Commission (IATTC, 2004). Fish were randomly subsampled from purse-seine sets immediately after capture, and date, position, and sea-surface temperature (SST) were recorded for each set that yielded samples. Observers measured fork length of the fish, removed samples of white muscle tissue from the dorsal musculature adjacent to the second dorsal fin and stored them at about -20 degrees C until processed further in the lab. Data is in predator-prey format where each row represents a unique predator-prey observation.

Source

Olson RJ, Popp BN, Graham BS, Lopez-Ibarra GA, Galvan-Magana F, Lennert-Cody CE, Bocanegra-Castillo N, Wallsgrove NJ, Gier E, Alatorre-Ramirez V, Balance LT, Fry B (2010) Food web inferences of stable isotope spatial patterns in copepods and yellowfin tuna in the pelagic eastern Pacific Ocean. Prog Oceanogr.

IATTC, 2004. Annual Report of the Inter-American Tropical Tuna Commission, 2003. Inter-American Tropical Tuna Commission, pp. 98.

pkuhnert/diet documentation built on June 10, 2025, 2:59 a.m.