Caribou and the Kuskokwim

Caribou have roamed in the Kuskokwim area for thousands of years and were a traditional food source for the region’s inhabitants. These caribou eventually came to make up the Mulchatna herd (MCH), named after their calving grounds near the Mulchatna River. In the 20th Century, reindeer were introduced to the area. Caribou and reindeer are the same species of animal, but they are given different names depending on where they came from. Caribou are wild and native to Alaska, but reindeer were introduced later, and they can be domesticated. This section provides an overview of both caribou and reindeer in the Kuskokwim.

Caribou held important status as more than just a food source in Alaska Native culture. Yup’ik fans made of caribou hair are just one example of the ceremonial significance of caribou. Denai’na and Yup’ik cultures reference caribou in their teachings and storytelling, and this knowledge passed sustainable management techniques through generations. First contact with Europeans occurred in 1844 in McGrath after the arrival of Russian explorers, and the expanding pressures of colonization reshaped the region. Market forces, mining ventures, and increased administration all disrupted daily life. The US government introduced reindeer herds which also affected the role of caribou.  

“Caribou was just starting to come around when I first come, that was ‘60 when caribou, when I got my first caribou. There was a lot of caribou right out close.”

“Yeah. I don’t remember where they went hunting. I know caribou, they hunted ... a lot of times, right around Georgetown in those hills, there was a lot of caribou or they would fly up to grandpa’s sheep camp ... Windy Fork, they’d get caribou and sheep up there. Moose ... I’m thinking probably up towards the Holitna, up the George River and maybe even over on Innoko, where grandpa has ... his land at”  “In like the seventies, possibly eighties ... caribou was all over, down there, Georgetown, around between Red Devil and Georgetown, Eight Mile was one of their main crossings, remember? And now for years, we have not seen a caribou down in that country. Not like it used to be”

“Yeah they were all over there”

A report on Traditional Ecological Knowledge of the Middle Kuskokwim stated that “caribou were probably the most abundant large land mammal” in the current Mulchatna herd range before the 20th century. Moose only “became a primary subsistence resource” in the area in the mid-1900s, replacing caribou. 

We know the caribou population fluctuated even in the 1800s. A decline started from the late 1800s into the early 1900s coincided with the introduction of Siberian reindeer herds. The most accurate population numbers for the Mulchatna herd begin in 1949, but Kuskokwim residents “said that efforts to hunt caribou were continual despite fluctuating conditions” of the herd.

In parallel, the federal government started a reindeer herding program. According to June Alaska (Twitchell) McAtee, the federal government hired Saami people from Finnmark, Norway to teach and establish a culture of herding reindeer in Alaska starting in 1894. They also imported reindeer from Siberia in what was known as the “Alaska Reindeer Project.”

The program began in the Seward peninsula, but herders spread outwards with some bringing about 200 reindeer to the Kuskokwim region. The group arrived in Bethel in late 1903, and as they settled into the region, herders became an important part of the mining economy by providing food to the local population. 

Two Saami families established herds in the Kuskokwim area, one “grazing … in the Kuskokwim and Aklun mountains, and east-ward into the Tikchik Lakes region,” while “several separate herds grazed ranges on the Kwethluk, Kisaralik, Fog, Salmon, and Aniak rivers, all tributaries of the Kuskokwim.” These reindeer were more than just a food source. They provided a mode of transportation that could forage, so they did not require travelers to stock extra food supplies.

Saami reindeer stewardship ended in 1937 with the passage of the Reindeer Act, which restricted reindeer ownership to Alaska Natives. Nonetheless, the Saamis brought their traditions of maintaining reindeer as a resource and contributed to the cultural and economic expansion of the region as the mining industry developed.  

Currently, there are only a handful of reindeer herds managed in Alaska by Native people, including in Nome and on Nunivak Island. 

This figure shows the number of caribou documented within the study area for each year of data available. According to the graph, the MCH population in 1970 was estimated to be 5,000. After increasing steadily through the 1980s, the population estimate reached 200,000 by 1996. Neil L. Barten says the leading causes of the increase were “a succession of mild winters, movements onto previously unused range, relatively low predation rates, and an estimated annual harvest rate of less than 5% of the population since the late 1970s.  

By the summer of 2008, the MCH population declined by 85% from this peak to about 30,000 caribou. And, in 2017 there were approximately 25,000-30,000 MCH caribou in the study area. A recent newsletter from the Alaska Department of Fish and Game estimates that the herd was down to around 12,100 caribou in 2022. This small population sits far below the ADF&G population goal of 30,000-80,000 caribou in the herd.  

To understand the Mulchatna herd’s recent decline, it is necessary to understand the interdependencies within the MCH ecosystem. A report by Barten says that during the decline, the herd had an older age structure, low productivity, and higher calf mortality. Combined with overgrazing, the MCH population began to decline. As malnutrition snowballed into even lower productivity and the spread of disease, the herd became more vulnerable to predators.  

Researchers studying Mulchatna calves found that predators caused the most calf deaths soon after birth. A newsletter from 2021 says the largest causes of death unrelated to predators were “starvation and drowning.” 

The following images come from the same study about traditional ecological knowledge of the Mulchatna herd. As we progress through the years, notice how the herd expands outwards, losing its density over time.

This first image comes from the 1980s, as the herd was still growing in size. Notice the concentration on the eastern part of the study area, right along the Mulchatna river.

At this point the Mulchatna herd reached its peak. The top left corner of this image show that the population climbed until bout 1996, where the population reached 200,000 caribou. The old range could no longer support this many animals, so the caribou expanded outwards into a much larger area that included much of the Kuskokwim river.

The population continued its decline from its high point in the 1990s, but the territorial expansion continued from that period. Mulchatna caribou maintained a wide range, but they were even less concentrated than they were in the previous decade. By the end of the 2010s the herd fell to less than 50,000, and the herd has not reached that amount since then.

This data does not stretch to the present day, but it is the last map we have of the caribou distribution in the region. Population numbers remained consistently low, and caribou roamed over a large area with fewer areas of high concentration than in previous years.

The Mulchatna herd scattered over time, decreasing in concentration as the population dramatically fell.

As shown by the concentration and scattering of the herd over the decades, even as the herd declined in numbers, the range of the caribou increased. The carrying capacity of traditional wintering areas, the number of caribou that they could support, was surpassed by 1986-8, forcing the herd to expand its range for survival. 

As caribou populations declined, locals observed that moose became increasingly available. It was only in the early 20th century that moose began to appear in Alaska’s tundra regions, previously occupied by caribou. Moose feed on deciduous shrub vegetation, which expands when lichen regeneration is inhibited. As a result, as the landscape changes, there is more vegetation for moose to subsist on and less for caribou – one major driver of hunters switching from caribou to moose targets. And in some subsistence hunting communities in MCH range, moose have replaced caribou to fill that subsistence need. 

Declining population and increased regulation make the Mulchatna herd a less reliable source of subsistence food for people in the region. Moose harvests in the region have increased specifically among local Alaskan residents during that time, even as numbers from Alaska nonlocal residents and non-Alaska residents declined. This change reflects both the rising number of Moose in the region and the increased need for an alternate food source. 

Today, climate change continues to threaten ecosystems across Alaska. Mean annual temperature in the state has increased by 3 degrees F in the past decades, by 6 degrees in the winter – more than twice as fast as the US. By 2050, temperatures are expected to rise by another 2-4 degrees. Consequently, Alaska confronts:

1. Warming and thawing of permafrost
2. Changes in vegetation (including the expansion of boreal forests into tundra)
3. Increased landscape-level events like wildfires, drying lakes and wetlands, earlier snowmelt and later freeze-up
4. More frequent ice storms and rain-on-snow.

Given the interconnected nature of Alaska’s ecology, each disturbance amplifies the impacts of the others.

While research shows that it is regular for “barren ground caribou populations” like the Mulchatna herd to “experience large fluctuations between abundance and scarcity over the scale of decades,” researchers note that “changes in forage and habitat conditions” are the primary cause of population change, and that herd numbers are “less affected by predation or hunting.” Climate change is exerting profound influences on these herds’ habitat and will continue to do so.  

For example, because the availability of alpine and tundra habitat supports caribou, climate change is decreasing forage accessibility for the herd. Midwinter icing, such as rain-on-snow events, causes ice layers to form on lichen, which then becomes inaccessible to caribou. As a result, poor lichen availability in the winter can impact fetus development and reduce population growth of caribou. And as temperatures rise due to warming, shrubification, or the expansion of shrubs into previously tundra habitat, reduces the caribou-friendly vegetation as well.  

The story of caribou makes up a key part of the story of life on the Kuskokwim in the past and present, even as the region faces an uncertain future. While the caribou confront the effects of climate change on their habitat, the MCH will shift north in pursuit of warmer temperatures and accessible vegetation. 

For the people who have subsisted on caribou for generations, traditional food sources like caribou grow scarce. The “Adapting to Climate Change in the Middle Kuskokwim” document describes how “people are purchasing meat and shelf stable foods to augment subsistence diets” with the decline of salmon runs on the Kuskokwim, but the decrease in caribou is another factor forcing people along the river to move away from traditional food sources.  

Subsistence on a variety of sources, including salmon, is intrinsic to life on the Kuskokwim and its economy. Along with climate factors pressuring caribou subsistence, there are many other challenges to engaging in subsistence. One such challenge is the dual management system, where both the state and federal governments regulate subsistence in Alaska. This means that their regulations often conflict: while federal regulations recognize a rural priority, state regulations do not. These discrepancies result in complicated laws that Alaska Natives and subsistence users must make sense of.  

The lined yellow areas are Bureau of Land Management lands currently under review for future development. Many of these areas make up part of the current Mulchatna habitat, or they could become part of the future habitat as the herd moves north in response to rising temperatures. These management areas are only part of a patchwork of jurisdiction where state and federal agencies control different parts of the Mulchatna range. These agencies often have separate management objectives and obligations which can conflict with one another.

Differences in land management make it difficult to preserve large landscapes for the Mulchatna herd to roam, and the current patchwork system has the potential to disrupt migration patterns. Various management agencies and stakeholders will need to coordinate their response to the changing needs of the Mulchatna herd for it to have the best chance of survival in the coming years.

There is no one way to prevent the decline of the Mulchatna herd, and although predators pose some risks to caribou, they are not the only reason the population has fallen. As climate change intensifies, balancing resource development with conservation will be a major challenge.  

The conservation of large landscapes is vital to allow caribou herds to adapt to shifts in their environment. The establishment of protected spaces, as opposed to fragmentation, would ensure caribou could maintain and establish new migratory patterns.    

Wildfires can also pose huge risks to caribou habitats. Wildfires in tundra and caribou wintering areas can lead to shrubification, meaning these areas will never turn back to tundra. Shoring up wildfire suppression in critical regions will protect vital habitats and support caribou's continued subsistence.  

Ultimately, because caribou are one species in an ecosystem, collaboration will be necessary to protect the MCH herd. Multi-agency management coordination, stakeholder involvement, and an interconnected approach to species conservation will help the caribou as they face the intensifying pressures of climate change.