Evaluating the effects of giraffe skin disease and wire snare wounds on the gaits of free-ranging Nubian giraffe

DOI: 10.1038/s41598-023-28677-yRead our scientific commentary

Research by

Laura M. Bernstein‐Kurtycz, Noah T. Dunham, Janny V. Evenhuis, Michael B. Brown, Arthur Muneza, Julian Fennessy, Patricia M. Dennis, Kristen E. Lukas

The study quantifies limb and neck kinematics associated with visible snare wounds and skin lesions in free-ranging male giraffes.

Study summary

A snare wound can change the rhythm of a giraffe’s walk. Wire traps do not have to kill an animal to leave a lasting problem. A giraffe may remain mobile with an injured leg, but simply counting it as alive misses how differently it now moves. Skin lesions, another conspicuous problem in wild giraffes, might also interfere with movement.

Laura Bernstein-Kurtycz, Noah Dunham and colleagues compared video of 33 adult male Nubian giraffes in Uganda’s Murchison Falls National Park. They analysed 115 walking strides from animals with snare wounds, skin disease, both conditions or neither. Frame by frame, they measured stride length, speed and the timing of each foot touching and leaving the ground. They also examined neck movement in a smaller set of animals.

Giraffes with snare wounds walked more asymmetrically, spending less time supported on their injured side; those with snare wounds alone also took shorter strides and moved more slowly. Skin disease showed no significant effect on walking, but most lesions were around the neck, so that result cannot settle what severe leg lesions do. The videos reveal a cost of surviving a snare: walking can remain possible while its mechanics change.

Summary by The Last Giraffe

Publication details

Study facts

Method
Observational video kinematics; mixed models of disease and snare-wound presence.
Location
Murchison Falls National Park, Uganda.
Species
Nubian giraffe, Giraffa camelopardalis camelopardalis in the paper.
Sample
52 adult males filmed; limb analysis: 33 animals/115 strides; neck analysis: 29 animals/71 strides.
Period
July 2015–August 2016.

Full citation

Laura M. Bernstein‐Kurtycz, Noah T. Dunham, Janny V. Evenhuis, Michael B. Brown, Arthur Muneza, Julian Fennessy, Patricia M. Dennis, Kristen E. Lukas (2023). Evaluating the effects of giraffe skin disease and wire snare wounds on the gaits of free-ranging Nubian giraffe. Scientific Reports. https://doi.org/10.1038/s41598-023-28677-y

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Original abstract

Giraffe skin disease (GSD), a condition that results in superficial lesions in certain giraffe (Giraffa spp.) populations, has emerged as a potential conservation threat. Preliminary findings suggested that individuals with GSD lesions move with greater difficulty which may in turn reduce their foraging efficiency or make them more vulnerable to predation. A current known threat to some giraffe populations is their mortality associated with entrapment in wire snares, and the morbidity and potential locomotor deficiencies associated with wounds acquired from snares. The goal of our study was to quantify the locomotor kinematics of free-ranging Nubian giraffe (G. camelopardalis camelopardalis) in Murchison Falls National Park (MFNP), Uganda, and compare spatiotemporal limb and neck angle kinematics of healthy giraffe to those of giraffe with GSD lesions, snare wounds, and both GSD lesions and snare wounds. The presence of GSD lesions did not significantly affect spatiotemporal limb kinematic parameters. This finding is potentially because lesions were located primarily on the necks of Nubian giraffe in MFNP. The kinematic parameters of individuals with snare wounds differed from those of healthy individuals, resulting in significantly shorter stride lengths, reduced speed, lower limb phase values, and increased gait asymmetry. Neck angle kinematic parameters did not differ among giraffe categories, which suggests that GSD neck lesions do not impair normal neck movements and range of motion during walking. Overall, MFNP giraffe locomotor patterns are largely conservative between healthy individuals and those with GSD, while individuals with snare wounds showed more discernible kinematic adjustments consistent with unilateral limb injuries. Additional studies are recommended to assess spatiotemporal limb kinematics of giraffe at sites where lesions are found predominantly on the limbs to better assess the potential significance of GSD on their locomotion.

Abstract by L. M. Bernstein-Kurtycz, N. T. Dunham, J. Evenhuis, M. B. Brown, A. B. Muneza, J. Fennessy, P. M. Dennis and K. E. Lukas. Evaluating the effects of giraffe skin disease and wire snare wounds on the gaits of free-ranging Nubian giraffe. Scientific Reports 13, 1959 (2023). Reproduced under CC BY 4.0. No author or publisher endorsement is implied.

Source abstract · Creative Commons Attribution 4.0 International (CC BY 4.0). Abstract text reproduced without changes; formatting adapted for this website.