Small bait traps as accurate predictors of dipteran early colonizers in forensic studies

Abstract

Insect carrion communities vary among habitats and over time. Concerning the dipteran early colonizers of carrion, the use of small bait traps should be accurate because the odors emitted from meat baits should contain many of the volatile organic compounds emitted from the freshly dead mammals. In addition, this kind of trap is easy to replicate and set in position in a given habitat. In the present study, small bait preferences of early Diptera carrion colonizers were examined in an urban biotope. Specifically, three baits were compared (pork muscle, pork liver, and fish flavored cat food) in respect to the number of specimens and species captured and the presence or absence of oviposition at high and low environmental temperatures. A total of 2371 specimens were trapped, primarily belonging to three insect orders, Diptera, Coleoptera, and Hymenoptera. Diptera was the predominant order, with blowflies (Calliphoridae) being the most representative family, followed by filth flies (Muscidae). The pork muscle bait was responsible for the highest number of captures and the highest diversity. The community of Diptera collected with the most efficient bait, pork muscle, was compared with the carrion communities reported in the literature from the Iberian Peninsula. Similar taxonomic species composition was found regarding Calliphoridae species. A specimen from all species morphologically identified were also identified at a molecular level using the cytochrome c oxidase I (COI) barcode region, and the sequences were submitted to online databases.

Small Bait Traps May Not Accurately Reflect the Composition of Necrophagous Diptera Associated to Remains

“…Passive data retrieval methods are widely used in different fields of research to reduce the investment in time and energy in obtaining information [ 1 , 2 , 3 , 4 ]. This trend is for example present in the field of forensic entomology, which is the study of the association between insects and corpses for forensic and legal purposes, often to determine the post-mortem interval (PMI) of a corpse [ 5 , 6 , 7 ].…”

“…This trend is for example present in the field of forensic entomology, which is the study of the association between insects and corpses for forensic and legal purposes, often to determine the post-mortem interval (PMI) of a corpse [ 5 , 6 , 7 ]. In this field of applied research, insect traps are increasingly used for the sampling of necrophagous Diptera [ 1 , 8 ], one of the key sarcosaprophagous faunal groups [ 5 , 9 ]. Different models of large and small bait traps have been developed, the more commonly used traps in forensic entomology being bottle traps, Schoenly traps, sticky target traps, wind-oriented traps, funnel traps, and bait bins [ 1 , 3 , 8 , 9 , 10 , 11 , 12 , 13 ].…”

“…Small bait traps are often advantageous compared to the human cadavers, vertebrate carcasses, or Schoenly traps because they emit a faint odor and there are no ethical, legal, or convenience implications associated to their use [ 1 ]. These traps mainly target Diptera, notably blowflies (Diptera: Calliphoridae), which are often the first arthropods to colonize carcasses [ 14 ].…”

“…These traps mainly target Diptera, notably blowflies (Diptera: Calliphoridae), which are often the first arthropods to colonize carcasses [ 14 ]. They are generally baited with a small amount, being 50–200 g, of various animal organs such as pork muscle, pork liver, beef liver, chicken liver, or squid [ 1 , 12 , 15 , 16 ]. Synthetic compounds such as sodium sulfide, which act as constant chemical attractants to necrophagous Diptera, may also be used as bait, often with pork liver [ 8 , 11 , 13 , 17 , 18 ].…”

Yaz Mevsiminde Samsun’daki Nekrofaj Diptera Çeşitliliği

“…Her tuzakta farklı yemler kullanılarak farklı böcek türlerine ait erişkinleri yakalamak için elverişlidir. Yem tuzakları basit ve hayvan karkaslarını içeren tuzaklara göre daha ucuz olmaları, her ortamda kolaylıkla uygulanabilmeleri, kimyasal madde içermemeleri, çevreye zararlı etkilerinin olmaması lojistik ve etik kısıtlamaları ortadan kaldırması gibi avantajlara sahip olduğu için kısa ve uzun süreli araştırmalarda çok sık tercih edilirler (10,11). Bu çalışmanın amacı, Samsun ilindeki yaz mevsimi boyunca adli açıdan önem arz eden nekrofaj Diptera takımına ait türlerini tespit etmektir.…”