BAWC 2016 Email Version

Post on 27-Jan-2017

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Who am I?

• BSc (Hons) Forensic Science Student

• Graduate in July with predicted 1st Class (hopefully!)

• Aspirations for a career in the Wildlife Crime sector

• Combination of my two passions: Forensic Science & Wildlife!

• Particular interest in protecting birds of prey

• Lifelong member of the RSPB and Norfolk Wildlife Trust

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• Red and Green magnetic fluorescent fingerprint powders deemed most suitable for feathers• Black magnetic powder most suitable for the surface of the eggs

Previous Research

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Definitions• Research focused on the visualisation of latent fingermarks

– Latent: Generally difficult to visualise (invisible); Principle component is sweat;

Vast majority of all fingermarks

• Fingermark or Fingerprint?– Fingermark: Impression left by the friction ridges of a human finger

(Non-Fingerprint Experts)

– Fingerprint: Impression left by the friction ridges of a human finger (Qualified Fingerprint Experts Only!)

• Ridge Detail: ridge flow and specific ridge characteristics

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Methods• Fingerprint powders and Superglue fuming

• Powders observed using different wavelengths of light and their corresponding filters

• Superglue fuming followed by Basic Yellow 40 staining

• Fluorescent observed under blue light (430-470nm)

• Used a grading scale to determine the quality of the developed print

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Results

Feathers• Red magnetic powder enhanced

88.6% of fingermarks

• Green magnetic powder enhanced 84.3% of fingermarks

• Mainly low grade marks (some ridge detail present)

• Finer weave count of feather = better quality ridge detail

• Least Successful: White magnetic powder and aluminium powder

Eggs• Black magnetic powder enhanced

95.8% of fingermarks

• High number of high grade fingermarks developed

• High grade marks = more ridge detail present

• 100% enhancement on raptor eggs (Goshawk, Barn & Long-Eared Owl)

• Least successful on raptor eggs: aluminium powder

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Our Research• Replicated techniques

• Deposited fingermarks on the top, underside and quill tip of the feather

• Tested more colours of fluorescent fingerprint powder

• Trialled the combinations of powder and wavelength of light to determine the best contrast

• Used Superglue fuming followed by two types of stain

• New methodology

• Examined efficiency of Ninhydrin & DFO

• Additionally tested the effect of Small Particle Reagent (SPR)

• Looked at the effect of separation/repair

• Ensured each fingermark was deposited with the same amount of sweat and pressure

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Results – Magnetic powderGreen Powder + UV light: Dark Feather

Green Powder + UV light: Waterfowl Feather

Combination worked well on three feather types:

• A white, waterfowl feather

• A patterned Tawny Owl feather

• A dark, banded feather

The darker the feather, the better the contrast!

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Results – Superglue Ninhydrin & DFO

• Waterfowl Feathers– Basic Yellow 40 Stain –

Enhanced 7 out of 8 marks under blue light (430-470nm)

– Saffranin Stain – One mark (no ridge detail) under blue light

• Tawny Owl Feathers– Basic Yellow 40 Stain – No

enhancement– Yellow SPR – One mark, no ridge

detail– Green Fingerprint Powder + UV –

Enhanced all marks

• Concluded an unsuccessful “wet” treatment

• Chosen due to being fingermark development techniques for porous surfaces

• Feathers were dyed by the Ninhydrin reagent (purple) with no fingermark development

• No fingermarks were developed under DFO

• Concluded as unsuccessful development techniques for feathers

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Results – Small Particle Reagent (SPR)

• Liquid reagent caused problems with non-waterproof feathers

• Feathers needed to be re-spread and dried prior to examination

• Developed low grade prints (limited ridge details)

SPR + White Light: Tawny feather

SPR + UV Light: Tawny feather

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Effects of Separation• Two methods tested:

– Depositing a mark followed by separation of the feather – Separating the feather followed by depositing the mark

• Marks were enhanced with green fingerprint powder and SPR

• Detail was lost if mark separated after SPR enhancement

• Green fingerprint powder could be separated

• Separation and subsequent repair dependent on the texture of the feather

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Developed Mark, Separated Mark & Repaired Mark

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Conclusion

• Green magnetic fingerprint powder examined under UV light (350-380nm) most successful technique

• Small Particle Reagent most successful “wet” treatment

• Location of the mark on the feather is an important factor– Further from quill = clearer, more detailed fingermarks

• Texture of the feather effected enhancement and separation– Softer, “fluffier” feathers = less clear fingermarks– Thicker barbs of feather = more likely to be separated and repaired