On Elephants and Dirt: Conserving an Elephant Tracking Collar

Why is there an elephant collar in the Smithsonian’s National Air and Space Museum’s collection? Why does it look a little dirty: did the Museum forget to clean it?

The collar came into the Emil Buehler Conservation Lab at the Steven F. Udvar-Hazy Center for documentation and treatment before going on display in the upcoming new and reimagined galleries at the National Mall building. It was given to Museum by the Smithsonian’s Conservation Ecology Center at the Smithsonian’s National Zoo and Conservation Biology Institute.

The elephant tracking collar is in the Museum’s collection because it illustrates one of the many applications of space age technology: satellite communications. Devices like the collar can be placed on animals to track their movements and aid scientists in the study of animal behaviors. This is a non-invasive method that allows researchers to obtain information remotely and nearly instantly from out in the wild.

Several other animal tracking collars will also be on display at the Museum, such as an oryx collar the Innovations: Climate Change gallery, as well as collars for a shark and a bird. These all demonstrate the applications of satellite tracking technology and its different scientific research applications.

The elephant tracking collar was manufactured by Telonics. Considering the size of elephants, all such collars need to be large and made of durable materials robust enough to withstand elephants’ normal physical activities. Within the casing at the center of the collar is a GPS sensor, a battery, a VHF beacon antenna, and a transmitter. Antenna wires are laced inside the arms of the collar. These technologies together collect data about an animal’s activity, temperature, and geolocation. In addition to providing information that informs scientists about their behavior, the geolocation reference can be helpful when combating illegal poaching of elephants or aiding in the mitigation of human-elephant conflicts in areas where the forests and agricultural land abut.

The Smithsonian has a long history of working with wild elephants in Myanmar in collaboration with Burmese partners. The tracking collars help collaborators inform local people about elephant movements to both protect elephants and protect people’s livelihoods. Read more about the Smithsonian’s work in Myanmar with wild elephants and tracking collars via the National Zoo’s website and on Smithsonian Magazine online, and watch a film series produced about the human-elephant conflict in Myanmar (warning: links contain some graphic images).

How Does a Scientist Retrieve a Collar?

Elephants eventually manage to shake off collars, and the NASM collar met the same fate in Myanmar. Scientists or their collaborators gather the fallen collars and bring them out of the jungle back to their research stations. The collar is cut at the time of retrieval because only the batteries and electronic components are needed for potential reuse—the length and weight of the belting make it awkward and heavy to carry out of the jungle. The collars can be ordered in customized lengths up to 13 feet. Cutting it is also advantageous for the Museum’s purposes: the original collar size would have required a very large footprint in an exhibition case given the size of an elephant! Its current length is 59 inches.

What Do Conservators Do with a Collar?

Conservators study the collar, documenting its construction, materials, and notes about its current condition. With expertise in materials science, conservators identify materials present and try to predict and then prevent any problems that may arise when different materials interact on an artifact. The collar is made of a thick webbed textile that is laminated between two layers of brown resin. There is a projecting casing at the center of the collar that houses the electronic components. Due to wear in the dusty forest environment, the collar was coated with a light layer of dirt and other biological matter when it was collected. Some of the dirt had collected in the recesses, and in crevices where the collar overlapped. A lot of this type of dirt was loose and would easily come off with a brush. Some of the other dirt, however, was compacted and not easy to separate from the collar.

When new, the electronics casing at the center of the collar would have been completely sealed. Close inspection revealed that the seal between the casing and the collar had broken, resulting in a small gap between the casing and the collar. Dirt had gathered in this gap while worn by the elephant or during the time the collar had fallen to the ground before being collected. This dirt was compacted and appeared to be pressing on the casing, forcing the gap to widen further.

Dirt and biological matter are usually considered harmful to artifacts. Dirt is abrasive and can cause damage over time on a chemical or physical level. Gritty particles have sharp edges that could abrade and cut into the collar when the collar is moved or manipulated. Dirt can also attract and absorb materials from the atmosphere that, together with moisture, can initiate harmful chemical reactions.

On the other hand, dirt can also be informative. On archaeological objects, researchers can learn ecofacts, that is, demonstrations of interactions between the environment and the human or animal populations, such as types of food sources, pollen samples, or soil fertility. Dirt can also allow researchers to learn the chemical composition of the soil at the origin site, even enabling an archaeological site to be dated. Sometimes the choice may be to allow the dirt to remain on the artifact to show a history of use, for example, a residue in a ceramic bowl or a tool used during a scientific expedition. See the blog on maintaining evidence of use history on the iconic “Rosie the Riveter” drill. Another type of dirt from further afield—lunar dust—is generally preserved on the Museum’s artifacts because it is considered an important part of the object’s history.

In the case of the elephant collar, Museum conservators and curators had discussions about whether to remove the dirt from the collar. Allowing the dirt to remain demonstrates the everyday use of the collar and is faithful to the fact that the collar is not new: it was worn by an elephant and had a life out in the wild. The team also wondered how much dirt had entered the battery pack and whether that was potentially causing harm to the object.

Museum conservator Lauren Horelick and Engen conservation fellow Lindsay Cross took X-radiographs of the collar to assess the integrity of the battery pack. The X-radiographs showed that the battery pack remains sealed. This determination helped the team choose to leave the compacted dirt in the battery pack, reasoning that the dirt has done all the damage that it is likely to do. Trying to remove all the dirt from within the casing would have required a more interventive treatment, that is, trying to break open the parts of the casing that remain sealed with epoxy to gain access. In this case, it seemed like trying to remove the dirt could cause more harm to the collar than good.

In the end, conservators and curators decided to also leave the dirt and biological matter that is present on any external surface as evidence of the collar’s use and history. Loose dirt in crevices and overlaps was removed to prevent any further abrasion to the collar’s surface.

Museum staffers together to design a specialized mount for the collar. It is displayed on an arc-shape to portray the curvature of the collar, and to suggest the rounded shape of an elephant’s neck. The tracking unit is in the middle of the collar and is displayed upright. The mount style is similar to that used for jewelry, for example a ring with a jewel in the center, but here it is scaled up for the size of an elephant’s collar!

The collar shows just one branch of the applications both near and far afield of space age technology, and the dirt present on it serves as a reminder of how far the collar has traveled, literally and figuratively, to arrive in its Museum case. The collar will be on view when the National Mall building’s east-end galleries reopen.