Observations on effects of feral pig (Sus scrofa) age and sex on diet

Abstract

Context Feral pigs (Sus scrofa) are a destructive invasive species that cause damage to ecologically sensitive areas. Management of biodiversity and of feral pigs assumes the diet of pigs of different ages and sexes are similar. Aims We aimed to investigate effects of feral pig age and sex on broad feral pig diet to identify potential at-risk native wildlife species so as to improve biodiversity and feral pig management. Methods Diet was determined by macroscopic analysis of the stomach content of 58 aerially shot feral pigs of mixed ages and sexes. The study occurred in the Macquarie Marshes, New South Wales, a Ramsar wetland of international significance. Results Feral pigs were largely herbivorous, with vegetable matter being found in all stomachs and contributing to a majority of the food material that was present in each stomach, by volume. Adult feral pigs had significantly more grasses and crop material in their stomachs than juveniles, while juveniles had significantly more forbs in their stomachs than adult feral pigs. Vertebrate prey items included frogs, lizard and snake, but no threatened wildlife species. Conclusions Juvenile and adult feral pigs differed in their diet, especially with regards to plant material, which has not been reported previously. There was, however, no difference in the consumption of vertebrate wildlife species between juvenile and adult, or male and female feral pigs. Slow-moving, nocturnal amphibians and reptiles were the most common vertebrate item recorded. Implications Biodiversity and feral pig management should recognise plant diet differences between demographic segments of the feral pig population. Further research is recommended to determine if diet differences also occur for threatened wildlife species, which will require more intensive nocturnal sampling.

Feral swine Sus scrofa: a new threat to the remaining breeding wetlands of the Vulnerable reticulated flatwoods salamander Ambystoma bishopi

“…There have been reports of feral hogs consuming amphibians at other locations, and their ability to consume large numbers of amphibians during mass migrations to or from breeding sites is a concern, especially for species limited to only a few remaining breeding sites (Schley & Roper, 2003; Jolley et al, 2010; Wishart et al, 2015). Feral hogs may also degrade the quality of breeding habitats by disturbing vegetation, spreading invasive plants, altering invertebrate communities (which are both important prey and predators of salamanders), reducing dissolved oxygen, and altering the microtopography (e.g.…”

A comparison of fragmenting lead-based and lead-free bullets for aerial shooting of wild pigs

“…Aerial shooting is widely used for wild pig control in Australia [ 11 , 12 ], the US [ 19 , 25 ], New Zealand [ 26 ], and many offshore islands [ 27 ]. Conservation estate inhabited by wild pigs that is often targeted for aerial shooting include sensitive wetlands such as RAMSAR sites (wetlands of international importance) [ 28 ] where obligations exist for land managers to minimize the presence of pollutants such as lead and other heavy metals [ 29 ].…”

Diet composition of the Korean wild boar Sus scrofa coreanus (Suidae) at Mt. Jeombongsan, Korea

“…According to previous studies, the diet of wild boar can be variable, depending on the accessible food sources (Herrero et al 2006). They are generally known as omnivores that mainly eat plants, but some researchers have reported them engaging in predation or active hunting (Wilcox and Vuren 2009;Wishart et al 2015). Wild boars have various diet habits and food preferences depending on their habitat type, and take different trophic functions and play roles in various environments (Ballari et al 2015).…”

“…Protein deficiency due to breeding can be one factor that causes females to consume food selectively. In addition, differences in body size as well as sex can be attributed to differences in plant food sources (Wishart et al 2015). Wishart et al (2015) reported that adults forage a lot of grasses and crop materials compared to juveniles.…”

“…In addition, differences in body size as well as sex can be attributed to differences in plant food sources (Wishart et al 2015). Wishart et al (2015) reported that adults forage a lot of grasses and crop materials compared to juveniles. In contrast, juveniles tend to consume more forbs that are easier to digest.…”