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Food webs developed under classical theoretical models often depict simplistic interactions among trophic levels linked by predation (Hairston et al. 1960). As a result, extensive research efforts have been devoted to studying predator-prey interactions, often ignoring the contribution of scavenging in food-web dynamics. However, recent advancements in food-web theory have recognized the widespread and critical role that scavenging plays in stabilizing food webs in ecosystems throughout the world, thus suggesting that previous models may have greatly underestimated the importance of scavenging in food web research ( Wilson and Wolkovich 2011; Barton et al. 2013). Such disregard for the importance of scavenging likely stems from a number of factors, such as human aversion to decomposing matter, difficulties in identifying scavenged versus depredated materials, and the fact that most species utilize carrion opportunistically (DeVault et al. 2003). Nonetheless, recent population declines of a number of obligate scavengers (e.g., vultures) have drawn international attention to this important group of species, and have sparked a renaissance in research on scavenging (Koenig 2006; Sekercioglu 2006; Ogada et al. 2012a; Moleón and Sanchez-Zapata 2015; Buechley and Şekercioğlu 2016a, 2016b; Ogada et al. 2016). ; This work was partially funded by project CGL2012-40013-C02-02 Spanish Government. The input of James C. Beasley was supported through funding provided by the US Department of Energy under Award Number DE-FC09-07SR22506 to the University of Georgia Research Foundation. This work has partially been funded by the Spanish Ministry of Economy and Competitiveness through grant no. CGL2012-40013-C02-01/02 MIMECO and FEDER funds. ; Peer reviewed

The crucial role of scavengers in ecosystem health
Animal scavengers' role in maintaining ecosystem balance is often overlooked. Dr Laurel Lynch from the University of Idaho tells us about her important research on how scavenging by Tasmanian devils influences ecosystem processes. Declines in biodiversity threaten the function of ecosystems worldwide. Species populations have declined by ~68% globally since 1970, and humans and their livestock now account for ~97% of Earth's biomass. Declines of top predators and scavengers are of particular concern because their loss can have devastating impacts on ecological and economic services, including secondary declines of other species, increases in disease spread, and changes in nutrient cycling that can affect food production. However, more research is needed to understand how the complex interactions among species and their environment produce the balanced, well-functioning ecosystems upon which humans depend.

An early morning at Bryant Salvage, a Vietnamese recycling business, finds a variety of San Francisco's scavengers converging to sell their findings. Vehicle after vehicle enters the yard to be weighed on the huge floor scale before dumping its load in the back; ancient pick‐up trucks with wooden walls, carefully loaded laundry carts, canary Cadillacs stuffed to overflow with computer paper, the shopping carts of homeless men, a 1950s ambulance carrying newspaper, and even the occasional gleaming new truck. The homeless men unload their towers of bottles and cardboard while young Latino van recyclers shout jokes across them. Middle aged Vietnamese women in jeans and padded jackets buzz around on forklifts or push around great tubs full of bottles and cans, stopping occasionally to help elderly people with their laundry carts. The van recyclers repeatedly honk their horns at the homeless guys to get out of the way. The homeless recyclers, silently methodical in their work, rarely respond.

This paper examines one aspect of noncapitalist production: that of raw materials from wastes in Bandung. Scavenging as an occupational group is defined and distinguished from other occupations involved with waste. The specification of Bandung scavengers as peasants has apparent implications for their development. (Overseas Development Administration)

The role of the offcuts of harvested kangaroos as a food source for native and introduced scavengers and detritivores was examined in the Roxby Downs region of arid South Australia. Corvids were the prominent users of offcuts in January and eagles and foxes significant users in September. Meat ants and a suite of carrion-specialist beetles and maggots also assisted with the decomposition of kangaroo offcuts. Harvested kangaroo populations provided a more reliable and better utilised food resource for scavengers and detritivores than did kangaroos that died naturally of heat stress. Kangaroo harvesting probably supports elevated populations of foxes, corvids, wedge-tailed eagles and detritivores. Therefore, kangaroo harvesters have a responsibility to control foxes, particularly in regions where endangered mammals or lambs are present.