Lanternfish (Myctophidae) Zoogeography off Eastern Australia: A Comparison with Physicochemical Biogeography

Abstract

In this first attempt to model the distributions of a mesopelagic fish family at this scale in the eastern Australian region (10°S to 57°S), lanternfish species occurrence data spanning a period from 1928 to 2010 were modelled against environmental covariates. This involved: (1) data collation and taxonomic quality checking, (2) classification of trawls into “horizontal” (presence-absence) and “oblique” (presence-only) types, and classification of vertical migration patterns using existing literature and the species occurrence database, (3) binomial GAMs using presence-absence data for representative temperate, subtropical and tropical species to examine depth interactions with environmental covariates and refine the selection of environmental layers for presence-only MAXENT models, (4) Presence-only MAXENT modelling using data from all trawls and the reduced environmental layers, and (5) Multivariate analysis (area-wise and species-wise) of the resulting matrix of logistic score by geographic pixel. We test the hypothesis that major fronts in the region (Tasman Front, Subtropical Convergence, Subantarctic Front) represent zoogeographic boundaries. A four-region zoogeographic scheme is hypothesised: Coral Sea region, Subtropical Lower Water region, Subtropical Convergence/South Tasman region and Subantarctic region. The Tasman Front, Subtropical Convergence and Subantarctic Front represented zoogeographic boundaries. An additional boundary at ∼25°S (coined the ‘Capricorn’ boundary) was adopted to delineate the Coral Sea from Subtropical Lower Water regions. Lanternfish zoogeographic regions are congruent with some aspects of two prevailing physicochemical biogeographic schema in the region, but neither of these schema alone accurately predicts lanternfish distributions. As lanternfishes integrate vertical ocean processes, the hypothesised lanternfish zoogeography may represent a useful model for a generalised pelagic biogeography that should be tested for other oceanic groups.

Biogeography of Micronekton Assemblages in the Natural Park of the Coral Sea

“…The strong latitudinal shift in micronekton assemblages found in our study mirrored Marshall (2013) andFlynn et al (2018) in bioregionalization of the eastern Australia region. Communities described in the present study were in agreement with previous studies in the Coral Sea with the dominant fish species belonging to the families Gonostomatidae, Sternoptychidae, and Myctophidae (Grandperrin, 1975;Flynn and Paxton, 2012;Sutton et al, 2017).…”

The contribution of migratory mesopelagic fishes to neuston fish assemblages across the Atlantic, Indian and Pacific Oceans

“…However, the distribution patterns observed and their relationship to surface and deep environmental factors are notable and deserve some comments. Myctophid occurrences in relation to temperature patterns have been commonly used to study pelagic zoogeography in particular oceans (Backus et al 1977, Hulley 1981Barnett 1984;van der Spoel and Bleeker 1991;Koubbi et al 2011;Flynn and Marshall 2013). All the adult myctophids collected in the survey were high oceanic species belonging to the mesopelagic community, whereas the only representatives of the bathypelagic community were a few larvae of Taaningichthys spp.…”

Fine-scale depth structure of pelagic communities throughout the global ocean based on acoustic sound scattering layers

“…Sayre et al 2017) or research applications. Biogeographies vary by depth strata, from surface and epipelagic classification (Longhurst 2007, Oliver & Irwin 2008, Spalding et al 2012, mesopelagic and water-column (Flynn & Marshall 2013, Proud et al 2017, Sayre et al 2017, Sutton et al 2017 to seabed (UNESCO 2009, Watling et al 2013. However, none have included detailed (10s of m) water-column community depth structure because data have not been readily available.…”