Investigations in LED lighting and the Mantella cowani to improve amphibian ex situ conservation efforts

UoM administered thesis: Master of Philosophy

  • Authors:
  • Chloe Helsey


Amphibians are in crisis. Threats to amphibians in the wild are numerous and widespread and thus, numbers declining at an alarming rate. Ex situ conservation efforts are increasingly being utilised to halt this decline and mitigate against external threats. Reintroduction is a crucial aspect of ex situ efforts, yet currently the success of these programmes are generally limited. A significant flaw in many of these ex situ conservation efforts is the insufficient knowledge of lesser-known vulnerable amphibian species that need to be brought into captivity. Increasing our understanding and gaining valuable information, for instance of the threatened Mantella cowani can provide guidelines to help inform ex situ programmes. In this thesis, the typical weight and size of M. cowani is outlined and a body condition index is determined. This will allow the fitness of individuals in captivity to be monitored ultimately maximising reintroduction success. Correct provisioning of environmental conditions within captivity is also crucial to the success of ex situ conservation programmes. Lighting in particular is an important environmental parameter for amphibians. Limited studies have investigated the use of visible lighting in amphibian ex situ conservation. The emergence of Light Emitting Diodes (LEDs), a highly attractive, alternative light source has highlighted the need for greater understanding of the current lighting provided. LEDs are a new form of economically and environmentally sustainable lighting, yet they have the potential to change the make up of captive environments. This study demonstrates the distinct differences between both the spectral and thermal output of LEDs and current lighting typically provided by zoological institutions. Subsequently, the impacts of these differences have been investigated. An increase in the activity of Mantella betsileo individuals under different LED treatments was observed. However, interestingly, the intensity of lighting rather than the spectral output could have a potential impact and play a greater role in the maintenance of healthy populations. Together, these preliminary studies provide an insight into the ways to in which ex situ conservation efforts can be monitored and improved and can help guide future investigations. It demonstrates the need for greater research into the provisioning of visible lighting in amphibian enclosures to enhance the success of ex situ programmes.


Original languageEnglish
Awarding Institution
Award date1 Aug 2017