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Bycatch is the most serious issue threatening the smalltooth sawfish today (Seitz & Poulakis 2006; NMFS 2009). The historical range of the species stretched along the coast from New York to Texas, but is now restricted to the coastal waters of Florida (Seitz & Poulakis 2006). Smalltooth sawfish populations have declined so drastically that an estimate by the National Marine Fisheries Service put the current number of animals at less than 5% of the individuals present during European colonization (NMFS 2009).

The South Asian river dolphin is divided into two subspecies, one inhabiting the Indus River of Pakistan (Indus River dolphin - Platanista gangetica minor) and the other the Ganges and associated river systems in India and Nepal (Ganges River dolphin - Platanista gangetica gangetica); a subpopulation of P. gangetica gangetica is also found in the Karnaphuli and Sangu Rivers of Bangladesh. Ganges River dolphins reside in the Sundarbans mangrove forest (India and Bangladesh) as well.

Historically, the whale shark has been hunted for its meat and liver oil. Whale shark fins are considered inferior in quality and the species is generally not targeted for its fins, although a market for them does exist in Asia due to their massive size (Norman 2005). Despite the fact that there is a paucity of data regarding whale shark bycatch, it is believed that the species most commonly becomes entangled in purse seines, longlines, and gillnets, particularly set nets.

Data from the Northwest Atlantic suggests that the thorny skate began declining in the early 1980s and accelerated in the early 1990s (Burgess et al 2005). In US waters, dredging for scallops also poses a risk (Packer et al 2003). Additionally, a targeted fishery for the species emerged in Canada in order to meet a growing European demand for skate wings (Kulka et al 2009). Bycatch in Canadian waters occurs on the Scotian Shelf, though landings do not equal those of the targeted fishery (Kulka et al 2009).

The Australian sea lion population decreased due to harvests in the 17th and 18th centuries and traditional subsistence hunting by aborigines (Goldsworhty & Gales 2008). Isolated reports of deliberate killings have persisted into the 21st century as well (DEWHA 2010). Although the species is now protected by Australian law throughout its range, recovery towards pre-sealing levels has been minimal (Goldsworthy and Gales 2008; AFMA 2010).

The white-chinned petrel is the most common avian bycatch species in the Southern Ocean (Weimerskirch et al 1999; Gilman 2006; Robertson et al 2006; Birdlife International 2013). The high bycatch rate is due to seabirds, such as petrels, being attracted to pelagic and demersal longlines by bait and offal discarded from vessels (Gilman 2006; Bugoni et al 2008) and the high incident of spatial and temporal overlap between petrel foraging grounds and areas of fishery activity (Delord et al 2010b).

The Endangered black-browed albatross is threatened throughout its range by commercial fisheries bycatch, primarily from longline vessels. Its vulnerability is due to the fact that, like other albatross species, the black-browed albatross is attracted to the easy food source provided by baited longline hooks, and consequently become hooked and drowned (Reid & Sullivan 2004).