In the mountainous terrain of the Bargy and Aravis massifs, you’ll often find the OFB (French Biodiversity Agency) out in the field, immobilizing and capturing the majestic Alpine ibex to test them for the disease brucellosis.

“After the capture, a veterinarian takes a blood sample that we can use for the rapid test. It works a bit like a COVID test and gives us a quick confirmation of the animal’s brucellosis status. If the animal is seronegative, it is marked and released, and if it is positive, it is euthanized while still under sedation. Then, the body is carried down for further testing in the laboratory,” Elodie Petit explains.

Brucellosis has been eradicated in most of Europe, but following an outbreak in a French cattle herd in 2012, linked to human cases, it was discovered that Alpine ibex in the Bargy massif were carrying the disease and had been doing so undetected, even though the disease had effectively been eradicated from livestock for over 10 years at that point. 

Photo credit: OFB

An important symbol

Brucellosis is a regulated disease and is subject to control measures for both public health reasons—since the disease can be transmitted from animals to humans—and economic reasons, as an infected cattle herd must be culled. Because this outbreak occurred in a region where a special raw-milk cheese is produced, maintaining a brucellosis-free status is paramount. However, the effort must also balance the welfare of the animals and the conservation of the species.

“The Alpine ibex is a protected species that is important to the people in the area. It is a symbol of the Alps and also stands as an example of how nature can be restored through reintroduction programs,” says Elodie Petit.

The Alpine ibex was nearly extinct in the Alps, but through reintroduction programs in the 1960s and 1970s, 178 large colonies are nowadays present in the Alps. 

A challenging immobilization

Monitoring the health of Alpine ibex in these massifs is far from simple. The animals thrive in the rugged terrain of the Alps, and although much of the work is organized in the spring when the animals graze in lower-lying areas, the mountainous terrain remains a significant factor. Females are the most frequent source of brucellosis infection in ibex, but the females are also much harder to approach than males, which makes the task even more challenging.

Photo credit: OFB

“Sometimes we’re obliged to dart from 45 meters, but in general we try to get closer, about 15 to 35 meters. The immobilization is challenging for several reasons, one being that we want the animals to be vigilant enough to not fall off a cliff.”

Up to five teams are in the field at the same time carrying out captures and tests. Each team consists of three OFB agents and a veterinarian. Among the OFB staff, one is a shooter and another one measures distance from the ibex with a rangefinder, taking slope into account. When shooting uphill or downhill, it is the horizontal distance to the target - rather than the straight-line slope distance - that determines your dart’s trajectory.

The team uses DANiNJECT equipment for their immobilizations.

“Often, we don’t have a lot of opportunities, so it's essential to have good immobilization equipment that we can rely on. When an ibex is sedated, we hold it down and put on a mask and shackles to secure all four legs. Then, the veterinarian takes the blood sample for the rapid test and other tests in the laboratory, and we also monitor their general condition and take biometric measurements.” 

Photo credit: OFB

Still questions to answer

When the efforts to stop the spread of brucellosis started, the disease was found in about 40% of the animals. Today, seroprevalence is closer to 10% but varies by sector.

“The interesting challenge is to fully understand how the disease works in the ibex population, so we can adapt our efforts in the best way. Even though we feel we understand a lot now, there are still pending questions we are looking for answers to,” Elodie Petit explains

Photo credit: OFB