Global Patterns of Predator Diversity in the Open Oceans

Temperature is a key factor in determining the distributions of adult tuna.

“Temperature is a key factor in determining the distributions of adult tuna (Worm et al. 2005, Boyce et al. 2008, Tittensor et al. 2010), as well as of larvae (present study).”

EKE has not been used to estimate larval habitats.

“Though EKE has been used in several studies to model the spatial distribution of adult tuna (e.g.Worm et al. 2005, Zainuddin et al. 2008), it has not been used to estimate larval habitats.”

Water temperature has repeatedly emerged as the best single predictor of species density and distribution.

“Of these, water temperature has repeatedly emerged as the best single predictor of species density and distribution (Lee et al. 2005, Worm et al. 2005).”

The selected tuna and billfish species share common ecological niches.

“These species were selected as they are all regionally heterothermic predators that share common ecological niches, are fished with like gear, and exhibit comparable oceanographic preferences (reviewed by Sund et al. 1981, Brill & Lutcavage 2001, reviewed by Worm et al. 2005).”

The selected tuna and billfish species are fished with like gear.

“These species were selected as they are all regionally heterothermic predators that share common ecological niches, are fished with like gear, and exhibit comparable oceanographic preferences (reviewed by Sund et al. 1981, Brill & Lutcavage 2001, reviewed by Worm et al. 2005).”

Community-wide patterns of abundance and richness of tunas and billfishes remain poorly understood.

“While tagging studies have added to our knowledge of the current ranges and distribution patterns for individual species of tuna and billfish (Block et al. 2001), community-wide patterns of abundance and richness remain poorly understood (Worm et al. 2005).”

Japanese logbook data are the only globally consistent data on species composition, catch, and effort for all tunas and billfishes.

“Japanese logbook data are compiled from the world's largest longline fleet and are the only globally consistent data on species composition, catch, and effort for all tunas and billfishes (Worm et al. 2005).”

The selected tuna and billfish species are all regionally heterothermic predators.

“These species were selected as they are all regionally heterothermic predators that share common ecological niches, are fished with like gear, and exhibit comparable oceanographic preferences (reviewed by Sund et al. 1981, Brill & Lutcavage 2001, reviewed by Worm et al. 2005).”

The selected tuna and billfish species exhibit comparable oceanographic preferences.

“These species were selected as they are all regionally heterothermic predators that share common ecological niches, are fished with like gear, and exhibit comparable oceanographic preferences (reviewed by Sund et al. 1981, Brill & Lutcavage 2001, reviewed by Worm et al. 2005).”

While temperature may be among the best global predictors for the distribution of these species, other factors are regionally important.

“While temperature may be among the best global predictors for the distribution of these species, other factors are regionally important (Worm et al. 2005).”

A decrease in species richness was documented in the western Pacific 'warm pool', where the highest mean annual ocean temperatures at 100 m (> 28°C) are found.

“A decrease in species richness was documented in the western Pacific 'warm pool' (Worm et al. 2005), where the highest mean annual ocean temperatures at 100 m (> 28°C) are found (Conkright et al. 2002).”

This latitudinal pattern is similar to that previously found for the diversity of tunas and billfishes, as well as foraminifera and other zooplankton groups.

“This latitudinal pattern is similar to that previously found for the diversity of tunas and billfishes (Worm et al. 2003(Worm et al. , 2005)), as well as foraminifera and other zooplankton groups (Rutherford et al. 1999).”

Longlines resemble long baited transects and catch a wide range of species in a consistent way over a vast spatial scale.

“Longlines resemble long baited transects and catch a wide range of species in a consistent way over a vast spatial scale and longline catch data have been previously used to analyse changes in abundance (Myers and Worm, 2003), diversity (Worm et al., 2005), range contraction (Worm and Tittensor, 2011) and biogeography (Reygondeau et al., 2012).”