Individual recognition of Eurasian beavers (Castor fiber) by their tail patterns using a computer‐assisted pattern‐identification algorithm

Abstract Individual recognition of animals is an important aspect of ecological sciences. Photograph‐based individual recognition options are of particular importance since these represent a non‐invasive method to distinguish and identify individual animals. Recent developments and improvements in c...

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Main Authors: Margarete Dytkowicz, Marcello Tania, Rachel Hinds, William M. Megill, Tillmann K. Buttschardt, Frank Rosell
Format: Article
Language:English
Published: Wiley 2024-02-01
Series:Ecology and Evolution
Subjects:
Online Access:https://doi.org/10.1002/ece3.10922
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author Margarete Dytkowicz
Marcello Tania
Rachel Hinds
William M. Megill
Tillmann K. Buttschardt
Frank Rosell
author_facet Margarete Dytkowicz
Marcello Tania
Rachel Hinds
William M. Megill
Tillmann K. Buttschardt
Frank Rosell
author_sort Margarete Dytkowicz
collection DOAJ
description Abstract Individual recognition of animals is an important aspect of ecological sciences. Photograph‐based individual recognition options are of particular importance since these represent a non‐invasive method to distinguish and identify individual animals. Recent developments and improvements in computer‐based approaches make possible a faster semi‐automated evaluation of large image databases than was previously possible. We tested the Scale Invariant Feature Transform (SIFT) algorithm, which extracts distinctive invariant features of images robust to illumination, rotation or scaling of images. We applied this algorithm to a dataset of 800 tail pattern images from 100 individual Eurasian beavers (Castor fiber) collected as part of the Norwegian Beaver Project (NBP). Images were taken using a single‐lens reflex camera and the pattern of scales on the tail, similar to a human fingerprint, was extracted using freely accessible image processing programs. The focus for individual recognition was not on the shape or the scarring of the tail, but purely on the individual scale pattern on the upper (dorsal) surface of the tail. The images were taken from two different heights above ground, and the largest possible area of the tail was extracted. The available data set was split in a ratio of 80% for training and 20% for testing. Overall, our study achieved an accuracy of 95.7%. We show that it is possible to distinguish individual beavers from their tail scale pattern images using the SIFT algorithm.
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spelling doaj.art-6dbc171f553343da932782998dffbb722024-02-29T08:56:40ZengWileyEcology and Evolution2045-77582024-02-01142n/an/a10.1002/ece3.10922Individual recognition of Eurasian beavers (Castor fiber) by their tail patterns using a computer‐assisted pattern‐identification algorithmMargarete Dytkowicz0Marcello Tania1Rachel Hinds2William M. Megill3Tillmann K. Buttschardt4Frank Rosell5FabLab Blue, Faculty of Technology and Bionics University of Applied Sciences Kleve GermanyFabLab Blue, Faculty of Technology and Bionics University of Applied Sciences Kleve GermanyDepartment of Natural Sciences and Environmental Health, Faculty of Technology, Natural Sciences and Maritime Sciences University of South‐Eastern Norway Bø i Telemark NorwayFabLab Blue, Faculty of Technology and Bionics University of Applied Sciences Kleve GermanyResearch Group Applied Landscape Ecology and Ecological Planning, Institute of Landscape Ecology WWU Münster Münster GermanyDepartment of Natural Sciences and Environmental Health, Faculty of Technology, Natural Sciences and Maritime Sciences University of South‐Eastern Norway Bø i Telemark NorwayAbstract Individual recognition of animals is an important aspect of ecological sciences. Photograph‐based individual recognition options are of particular importance since these represent a non‐invasive method to distinguish and identify individual animals. Recent developments and improvements in computer‐based approaches make possible a faster semi‐automated evaluation of large image databases than was previously possible. We tested the Scale Invariant Feature Transform (SIFT) algorithm, which extracts distinctive invariant features of images robust to illumination, rotation or scaling of images. We applied this algorithm to a dataset of 800 tail pattern images from 100 individual Eurasian beavers (Castor fiber) collected as part of the Norwegian Beaver Project (NBP). Images were taken using a single‐lens reflex camera and the pattern of scales on the tail, similar to a human fingerprint, was extracted using freely accessible image processing programs. The focus for individual recognition was not on the shape or the scarring of the tail, but purely on the individual scale pattern on the upper (dorsal) surface of the tail. The images were taken from two different heights above ground, and the largest possible area of the tail was extracted. The available data set was split in a ratio of 80% for training and 20% for testing. Overall, our study achieved an accuracy of 95.7%. We show that it is possible to distinguish individual beavers from their tail scale pattern images using the SIFT algorithm.https://doi.org/10.1002/ece3.10922Castor fiberEurasian beaverindividual pattern recognitionnon‐invasive mark–recapturescale‐invariant feature transformwildlife ecology
spellingShingle Margarete Dytkowicz
Marcello Tania
Rachel Hinds
William M. Megill
Tillmann K. Buttschardt
Frank Rosell
Individual recognition of Eurasian beavers (Castor fiber) by their tail patterns using a computer‐assisted pattern‐identification algorithm
Ecology and Evolution
Castor fiber
Eurasian beaver
individual pattern recognition
non‐invasive mark–recapture
scale‐invariant feature transform
wildlife ecology
title Individual recognition of Eurasian beavers (Castor fiber) by their tail patterns using a computer‐assisted pattern‐identification algorithm
title_full Individual recognition of Eurasian beavers (Castor fiber) by their tail patterns using a computer‐assisted pattern‐identification algorithm
title_fullStr Individual recognition of Eurasian beavers (Castor fiber) by their tail patterns using a computer‐assisted pattern‐identification algorithm
title_full_unstemmed Individual recognition of Eurasian beavers (Castor fiber) by their tail patterns using a computer‐assisted pattern‐identification algorithm
title_short Individual recognition of Eurasian beavers (Castor fiber) by their tail patterns using a computer‐assisted pattern‐identification algorithm
title_sort individual recognition of eurasian beavers castor fiber by their tail patterns using a computer assisted pattern identification algorithm
topic Castor fiber
Eurasian beaver
individual pattern recognition
non‐invasive mark–recapture
scale‐invariant feature transform
wildlife ecology
url https://doi.org/10.1002/ece3.10922
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