Chimpanzees have been listed on IUCN’s Red List of Threatened Species for over three decades, and have been recognised as an endangered species since 1996 as their populations continue to decline (IUCN, 2010). The future of this endangered species is uncertain and urgency to protect their habitat is acute.  Chimpanzees are important in their own right; however they also serve as a key umbrella, or focal, species for many other plants and animals that live in this dry forest. By protecting chimpanzee habitat, we will protect functioning ecosystems and diversity of natural resources that bring value to people.

Piel and Stewart participated in a 2011 workshop in Dar es Salaam to develop a Tanzanian Conservation Action Plan for chimpanzees identified the following key threats throughout chimpanzee range in Tanzania:

  1. Conversion of chimpanzee habitat into food crops and nonfood crop agricultural land:
  2. Incompatible extraction of firewood and logging for timber:
  3. Incompatible development and expansion of settlements and infrastructure:
  4. Incompatible human-ignited fires:
  5. Incompatible charcoal production:
  6. Disease due to pathogens introduced by humans and human activities:

Threats to the Ecosystem


Snares – Snares (left) remain a significant threat to local wildlife are the most common means of poaching wildlife. At Issa, at least two chimpanzees (both females) exhibit injuries that could have been caused by snares, which  range from bark cords for rodents to steel cables for buffalo. Monthly patrols outside the core study area help us (1) expand our coverage and monitoring of illegal human activity, (2) quantify the intensity of such activity for reports to local and regional authorities, and (3) confiscate bushmeat (see below).

 Below, Moritz frees a hartebeest that was ensnared south of Issa. We have also hosted game officers from Mpanda at the Issa camp to facilitate their patrols deep into the ecosystem, which is otherwise logistically inaccessible to patrols.

Forest clearing – Charcoal production is a cause of unsustainable deforestation in Tanzania. It occurs in the surrounding areas, but seems to be restricted to peripheral areas near villages. In collaboration with JGI, we  provided more than 500 fuel-efficient ovens to Uvinzan families. These stoves consume less fuel than traditional fireplaces. and reduce smoke inhalation by their users.


In 2009, we partnered with the Jane Goodall Institute to host government-led patrols for the first time. Government rangers patrolled the core study area with our staff . More recently, our surveys to the periphery of the study area resulted in good intelligence that we were witnessing an increase in illegal activity, mostly  herding and poaching. Consequently, we facilitated and supported further patrols by Mpanda government rangers. Guided by GMERC field assistants, rangers apprehended multiple teams of poachers and herders active along the periphery of the Issa Valley. Those apprehended were then transported to Mpanda police station. We continue to organise, facilitate and sponsor these patrols, which represent joint GMERC-government interests in protecting wildlife and its habitat throughout the ecosystem.

Government rangers escort illegal poachers out of the forest for arrest





Team, anti-poaching
GMERC members with Mpanda Forest Rangers (May 2015, credit S. Ramirez Amaya)












Additionally to anti-poaching efforts, we have partnered with TNC, FZS, JGI, and Tongwe Trust to train village forest scouts in the Ntakata Forest (see below) in September 2013. Six UPP staff in total traveled to Ntakata to train >18 scouts from three different institutions. Primary goals of this training were

(1)  To build capacity of forest monitors to better protect key areas of interest in the Ntakata forest;

(2) To improve monitoring efforts by standardizing data collection methods from a recent (2011-2012) survey of the GME (see below) that will allow us to compare wildlife abundance and threat intensity across GME regions, as well as to document unique species sightings, changes in forest condition, and overall provide continuous monitoring efforts of a critical ecosystem, where baseline data have already been collected by AP & FS. Stay tuned for photo-documentation once the training is complete!

Greater Mahale Ecosystem (GME) Chimpanzee Survey (2011-2013), and Monitoring (2014, 2017)

Alex and Fiona began this work in August 2011 and it ran through October 2012, designed to reveal the importance of target areas for chimpanzees, prioritize them across the GME, as well as describe the threats to these chimpanzee populations. We collected chimpanzee fecal samples at each site to examine questions concerning connectivity and gene flow across the GME. Additionally, the survey described the presence and abundance of other wildlife in these areas, including elephants (below, right). Logistics was consistently one of the greatest challenges to this work, with many areas inaccessible by vehicle. At left, porters carry equipment and supplies out of Ntakata forest (October 2011).

We continue this work to the present, now monitoring these high priority areas for any change in forest integrity or ape population over time. Most recently, Alex led a team back into Ntakata and Kalobwe forests in 2014, and Sebastian led a team to Wansisi in May 2015. The results of this monitoring work is being prepared for submission and eventual publication.

Porters carry equipment and supplies off the Ntakata Plateau







Alex with fresh bamboo feeding remains from chimpanzees in southeast Mahale Mountains National Park



A major focus of the GME survey has been connectivity, and whether chimpanzees across the GME represent a single, or multiple populations. Evidence here from southeast Mahale Mountains National Park suggests chimpanzees may range to the eastern border of the Park, and potentially into the Kashagulu Conservation Area, immediately adjacent.

Like at Issa, camera traps have helped reveal the presence of otherwise elusive chimpanzees and, potentially, their threats. For example, below a chimpanzee from northwest Ntakata Plateau was captured on video walking with what may be a snare injury to his left wrist.



Additionally, whilst chimpanzees abound in northwest Ntakata Plateau (see above), evidence of their presence was noticeably absent in the southern portion of the plateau. Below, Fiona stands above a riverine forest patch, amidst the rolling hills of Ntakata (June 2012).

1. …Are continuous from the eastern edges of Mahale Mountains National Park, across the Park border, and into Kalobwe Hills (see map above), where we began the survey in October 2011;

2. …Likely cross the Malagarasi river (see left), connecting the former Greater Gombe & Masito-Ugalla Ecosystems;

3. …Probably survive continuously in the mountains from Wansisi Hills near Katavi NP to Mahale NP, making what may be the largest continuous habitat for them OUTSIDE of National Parks in western Tanzania (see right).

GME Monitoring

In 2014/2015, Piel and Stewart were supported further by TNC/Tuungane (see below) to initiate monitoring efforts of key areas for chimpanzees across the GME.  Some areas – Ntakata and Kalobwe Forests, for example – showed no statistical difference in chimpanzee density after three years, whilst others (e.g. Wansisi Hills) showed a dramatic decline. Increases in agriculture and illegal logging at Wansisi adds further urgency to prioritising it as an area important to both endangered chimpanzees and also, potentially to elephants migrating to/from Katavi National Park. Below, Alex presents some of the findings of the survey results to the GME Steering Committee, a group comprised of District  government policy makers tasked with developing effective land-use plans across the region.

GME steering committee
Alex presents recent results to the GME Steering Committee in Mpanda (Dec 2015)

Tuungane continues to support terrestrial ecosystem monitoring by GMERC. In 2017, Adrienne Chitayat led teams back to key areas in the southern areas, whilst Richard Moore (LJMU) led teams into some northern areas to assess how chimpanzee abundance and habitat has changed over time. Stay tuned for results and updated figures on the health of chimpanzees across the GME!

Adrienne Chitayat, Noemie Bonnin and survey team members (May 2017, credit A. Chitayat)
The survey team at Wansisi Hills (May 2017, credit A. Chitayat)



Richard Moore, back from a 7 days survey to a peripheral area to Issa (credit: A. Henderson)


Surveys continue to reveal patterns of chimpanzee density and distribution across the GME. Monitoring of the northern MUE areas was completed in January 2018, with data collected not only on chimpanzee and other wildlife presence, but also complemented by a botanical survey.

Godfrey Stefano (above, right) leads the team in monitoring efforts of the MUE landscape, whilst Gabriel Simon Laizier (below) inventories the local flora


Tuungane Project

Data collected by Piel & Stewart from the GME survey will also be used in conjunction with an already-exisitng collaboration between with TNC, FZS, and Pathfinder Inc., called the Tuungane Project.

“To successfully conserve the Greater Mahale’s natural resources, protection efforts must focus on human and natural resilience. To reverse the trend of forest loss and coastal zone degradation, natural resource conservation must provide food security and sustainable economic growth for local communities. Without this growth and the diverse income opportunities it yields, people will have no choice but to continue to consume natural resources unsustainably.  This project is a multi-objective Population, Health and Environment (PHE) project designed to address the threats of human and natural communities for a sustainable future.”

Six strategies will be implemented in a geographically phased approach to improve health, livelihoods and natural resources protection in the Greater Mahale Ecosystem. Below Alex and Fiona participate at a recent Tuungane workshop in Mahale Mountains National Park, June 2012.

Other ways that GMERC is contributing to regional efforts at combating environmental degradation is by participating in workshops that concern village land use planning as well as a better understanding of the impact climate change will have on western Tanzania. Below left describes historical changes in rain patterns across Western Tanzania (from a report written by Elizabeth Gray, TNC), and right, participants at a March 2012 workshop.

Alex and Fiona at a Climate Change workshop in Kigoma, March 2012