Hydrology drives variation in spawning phenologies and diversity of larval assemblages of Australian wet–dry tropical fish

Abstract

This is an open access article under the terms of the Creat ive Commo ns Attri bution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Diverse parentage relationships in paternal mouthbrooding fishes

“…N. graeffei broods fewer eggs (1–88) and for a longer duration (four to five weeks) than G. aprion which broods 4–512 eggs for two to three weeks [ 17 , 18 ]. Spawning for N. graeffei occurs in the highly interconnected and productive wet season, while G. aprion spawns throughout the year, with higher occurrence during the wet–dry seasons, where young are exposed to habitat restriction and concentration of organisms (predators, competition) during the extended dry season [ 21 ]. In this study, G. aprion had considerable variation in genetic mating behaviour.…”

“…We investigate patterns of paternity in broods of two freshwater paternal mouthbrooders from divergent fish families, mouth almighty Glossamia aprion (Apogonidae) and blue catfish Neoarius graeffei. Although these species are fairly poorly studied, G. aprion spawns all year round, incubates for two to three weeks and has a fecundity of 104-532 and brood size of 4-416 eggs [16][17][18][19][20][21], Contrastingly, N. graeffei spawns during the wet season only, incubates for four to five weeks and has a fecundity of 4-128 and brood size of 1-88 eggs [17,18,21]. For both species, mouthbrooding comes at the expense of the parent's feeding, body condition and digestive and respiratory capacities [17].…”

Predictable hydrology, habitat and food resources determine fish recruitment dynamics in an incised tropical Australian river

“…This timing matches the dry-season peak in larval abundance and reproductive effort by adults of P. signifier, M. splendida and C. stercusmuscarum in incised Wet Tropics streams (Pusey et al, 2001(Pusey et al, , 2002(Pusey et al, , 2004, and the exotic tilapia (T. mariae), in the lower Mulgrave River (Russell et al, 2010). In the large Daly and Alligator river systems, Northern Territory, G. aprion displays aseasonal spawning and recruitment (Bishop et al, 2001;King et al, 2019;Tyler et al, 2021), with the presence of benign hydraulic conditions an important factor in recruitment success (Bishop et al, 2001). Low and stable baseflow during the dry season is a feature of the flow regime of central Wet Tropics rivers (Kennard et al, 2010;Pusey et al, 2004Pusey et al, , 2008.…”

“…Studies conducted in incised Wet Tropics streams show that small-bodied fishes (e.g., species of Melanotaeniidae and Atherinidae) spawn and recruit into the juvenile population primarily in the dry season when discharge is reduced and the incidence of spates is low (Pusey et al, 2001(Pusey et al, , 2002(Pusey et al, , 2004. In large river of the northern Australian wet-dry tropics, some species have a discrete spawning period aligned with the onset of the wet season while others spawn in both wet and dry seasons (King et al, 2019;Tyler et al, 2021). In northern Australia, studies on two diadromous species (Hypseleotris compressa and Megalops cyprinoides) show that spawning occurs primarily during the summer wet season, although the spawning location (i.e., fresh, estuarine or marine waters) and spawning stimulus are unknown (Davis, 1988;Pusey et al, 2004).…”

Identifying drivers of tropical riverine larval fish abundance and diversity

“…Larval fish data used in this study form a subset of those collected by Tyler et al (2021), whereby only daytime sweep net electrofishing (SNE; King and Crook 2002) samples were used. Sampling by SNE used a backpack electrofishing unit (model LR-20B; Smith-Root Inc., Vancouver, Washington, USA) with a 10 cm diameter anode ring fitted within a moulded plastic rectangular frame (25 cm × 30 cm × 2 cm), which held a 250 μm mesh sampling net and removable cod-end.…”