Deterrents are tools that try to stop cats from being successful killers. These can include collars, bells or other gadgets that make it hard to surprise prey or reduce their ability to pounce. Bells have often been suggested, but studies on efficacy have ambiguous conclusions about this method. Morgan et al, (2009) used radio-collars to study rates of predation, there was no significant difference in whether cats were wearing a bell or not. On the other hand, Gordon et al, (2010) found reduced predation in belled cats, when studied with a six week on, six week off split trial. Calver et al, (2007) carried out a similar study using the “CatBib”, a gadget used to reduce the cats ability to pounce, and found that the bib stopped 81% of bird predation, 33% of reptiles and amphibians predation and 43% of mammal predation. Nelson et al, (2005) studied use of sonic deterrence devices and found that the use of sonic devices produced 38% less mammal and 51% less bird predation. …show more content…
Trap‐Neuter‐Return (TNR) are trials in feral cat management that began in England and Europe in the 1950’s as an alternative to killing feral cats (Berkeley, 2004). The effectiveness of TNR has been debated, even though its use is expanding throughout the world. TNR is reported to have a number of benefits including; improved feral cat health, reduced public health risks, avoids the use of euthanasia, reduced risk to other cats, reduces threat of diseases (Hughes & Slater, 2002). However, TNR is has been reported to have negative effects such as; helps spreads disease (Mahlow & Slater 1996), affects ecosystem health (Loyd & Miller, 2010), impacts native predators (George, 1974), economic cost of surgery ( Mahlow & Slater, 1996), creates risks to public health (Hildreth et al, 2010) and has no clear ecological benefit (Guttilla & Stapp,