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The Zoological Lighting Institute maintains a charitable mission to support photobiology research through the arts for animal husbandry and wildlife conservation purposes. ZLI aims to achieve the AICHI targets of the UN Decade on Biodiversity, as it advances the highest standards in animal welfare in accordance with WAZA guidelines.

ZLI Mission and Goals

Animal Husbandry

Natural light is a fundamental environmental factor in the evolution and integral habitat of every animal on the planet. The complexity of photobiology relationships is substantial, and requires data driven research to fully understand. Understanding is necessary to animal care, in that the full range of natural animal behaviors depends upon an accounting of the environmental factors that contribute to them. Providing care that allows for as full a range of behaviors as possible is called 'enrichment'. The Zoological Lighting Institute is particularly interested in contributing to 'luminous enrichment', that is to say advanced practices that relate light cycles in managed situations to the fullest expression of natural behaviors possible.

Luminous enrichment in managed care is important. Animal husbandry, or the managed care of animals in ex situ conditions, is an indispensable practice necessary to for research, wildlife conservation advocacy, citizen science and cross-cultural education. Animals have been relocated from indigenous environments to new locations by humanity since time immemorial, and as long as humanity exists it will always be so. Caring for these animals requires skill, understanding and a great deal of effort to ensure that they are maintained in optimal conditions. Modified lighting conditions, and modified lighting cycles, inevitably limit the expression of natural behaviors. Yet we believe that data driven research can improve care substantially, in at least three ways. Animal physiology (the physical body of an animal), Sensory Ecology (how an animal maps the environment using available light), and Ecological Partitioning (when and where animals do what they do and how they relate to each other because of this 'spacing'), each have important implications for 'enrichment' possibilities in managed care situations.

To provide a ready resource, The Zoological Lighting Institute has created a simple template to collate existing and new research:

  • Animal Species
  • Physiology Research in Photobiology
  • Sensory Ecology Research
  • Photo-ecology Research
  • Case Studies from Managed Care

Wildlife Conservation

Natural light is a fundamental environmental factor in the evolution and integral habitat of every animal on the planet. Yet as the human population grows and expands, and as more an more artificial light is introduced into the environment, 'luminous' habitat is degraded and the capacity to support life is diminished. Limited lighting conditions, caused by the introduction of artificial light, limits the diversity of habitat and so the diversity and resiliency of life. Natural lighting conditions and many photobiology relationships can only be studied 'in situ'. Such research is necessary to conserve and manage species under threat of extinction or debilitation. Wildlife conservation, that is to say the active support of animal species for the protection of biodiversity and our human communities that depend upon it, is a necessary aspect of any truly sustainable development practice. Without wildlife, there is no life. The Zoological Lighting Institute supports in situ research for wildlife conservation, and links discoveries made in managed care to more informed approaches on how to manage light emission impacts upon wild populations.

Controlling light pollution is not difficult, but it requires commitment, public education and restraint. Typical approaches include the so-called 'low, long, and shielded' method, (mount lighting low, use primarily long wavelengths (red and amber in appearance), and the shield of exposed light sources from the sky). Another approach is the attendance to light reflections and the optical properties of materials rather than the addition of added artificial lighting. These are good strategies, but more exacting knowledge of in situ lighting relationships allows for the fine tuning of development to allow for wildlife to exist.

The best approach to preserving natural lighting, is to not add artificial light nor to modify environmental conditions by careless use of bird-killing glass or light-polarizing asphalt. Although there are times when such concessions to development seem necessary, they always must be balanced by consideration of global diversity and the human sustainability that depends upon it.

Photobiology Research

Data driven research is the key to success in wildlife conservation and animal husbandry, and in the creative reinterpretation of diverse human celebrations of light for sustainable community development. Visible light is unlike any other phenomena described in language, even other types of radiation. This is because in addition to being a physical property, it is integral not only with myth and allegory but human perception itself. Yet for the purposes of wildlife conservation and animal husbandry, it is absolutely essential to consider light from the perspective of the natural sciences, that is to say physical optics. Light relates to the physical conditions of animals in at least three ways. First, the ways in which it cycles and and surrounds the earth creates organic changes in the physiology and function of an animal's body. Second, many animals are able to exploit light in order to map space and so interact with, and navigate through, their environments. Third because natural light qualities are subject to both regular cycles and significant event-related changes such as fire or lighting, ecological relationships in space and time depend upon it.

The Zoological Lighting Institute™ segregates species specific photobiology research into these three categories:

  • Physiology
  • Sensory ecology
  • Ecological partitioning

This format enables for more exacting questions into how best to protect natural lighting conditions, or the 'luminous environment', and how to best care for animals in managed circumstances through 'luminous enrichment'.

Within these categories, data driven research is essential. The particular measures taken in photobiology are specific to what questions are being asked. Despite that, some generalizations are valid and, The Zoological Lighting Institute maintains protocols dependent upon them. For most processes studied in the science of photobiology, common short hand measures such as lux and foot-candles are irrelevant. It is necessary rather to measure the density of photons (energy packets of radiation) arriving at a given spot over time, and in most cases the frequency and/or polarization of these photons. A field and context rather than object, light can be expressed in this way as radiance, scalar irradiance or vector irradiance. The tool to measure such radiation is a 'spectro-radiometer', with appropriate light gathering attachments.

How light is measured in a particular setting depends upon the animal in question and the setting itself. In general, we recommend that general assessments take into account a large range of frequencies, from UVb through to infrared. Where there is cause to explore a specific relationship that can be handled in untranslatable short hand, such as near to far infrared ratios, this ought to be done for expediency, in addition to the broader data collection. As part of its certification programs, The Zoological Lighting Institute provides the appropriate tools as well as training in their use. However, the most important project we support is the ongoing data collection at a given location that goes well past the commissioning of certified projects. Peer review of data, and anecdotal case studies to go along with it, are essential to improving the state of knowledge today.

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