In partnership with the Maritime College of Forest Technology and Fundy National Park, the Fundy Biosphere Reserve (FBR) has been participating in a project aimed at assessing the moose population through aerial moose surveys in the FBR, and sharing moose population information with the public.
This year will be the third consecutive year that aerial moose surveys have been conducted in the FBR. Not only will the data collected from these surveys help to inform our understanding of the status of moose in our region, the surveys also provide an important training and capacity building exercise in the FBR. By defining and testing aerial survey protocols, and training the next generation of forest technicians and biologists, we are ensuring that our moose population will be well looked after for many years to come.
Ensuring the future of moose in the Fundy Biosphere Reserve not only depends on the collection of accurate population data, but also on the interest and support of the public. With funding from the Wildlife Trust Fund, our goal is to engage as many New Brunswickers as possible through our moose education and outreach program. To that end, we give presentations to naturalist and hunting clubs, we visit classrooms, and we write articles for a variety of special and general interest journals. We believe that an informed and engaged public is vital to the persistence of moose in our region. After all, it is our social, political, and economic interests that ultimately decide what a healthy moose population looks like! Check out the information provided in our online brochure, below.
The ecological role of moose
Moose are BIG animals; in fact, at 350-400kg on average, they are one of the largest land mammals in North America, second only to the bison by weight. Intuitively, moose are expected to play a significant ecological role in their surrounding environment, by virtue of their huge size. We can consider this role from two perspectives: first, their role in the ecosystem as consumers; and secondly, the role they play as food for other animals. If we consider these two roles together, we can think of moose as being an important 'go between' species that converts energy from plants into a usable form of energy for predators and scavengers. In other words, they move energy through the food web.
Moose as consumers
As herbivores, moose consume an incredible amount of plant material throughout their life time. In order to meet their energetic requirements, a single adult moose will eat up to 30kg of plants each day (1). This represents about 10,000 calories per day (1); which is a lot, considering you probably eat somewhere between 1500-2000 calories per day.
It's not just the quantity of food that moose eat each day that make them important consumers, however; they are also selective eaters, meaning that they prefer to eat certain kinds of plants over others. This is important because their food preferences can shape the distribution and abundance of plant species in the forest ecosystem. In the Acadian forest, moose prefer the tasty young shoots of maple, birch, and pin cherry in the summer and young shoots of balsam fir in the winter (2). The food preferences of moose can reduce- or eliminate- the occurrence of these species throughout their habitat. In this way, moose can directly affect forest regeneration processes and patterns of forest biodiversity (3).
Moose as prey
All of the plant energy that is consumed by moose will eventually work its way up the food chain, as moose themselves are an important food source for predators and scavengers. The greatest predator of moose in the Acadian forest- the wolf- has long been extirpated (locally extinct) in our region; the last wolf was killed in New Brunswick in 1876. Though the wolves are gone, there are black bears and coyotes in the Fundy Biosphere region, and these animals consume moose as both predators and as scavengers (2).
As predators, black bear are known to kill and eat newly born moose calves. About 10% of black bears in New Brunswick consume young moose in their diet, though the diet of bears varies regionally. For example, around Caraquet, New Brunswick, 80% of bears regularly consume moose calves. Most calves that are eaten by bears are less that 1 week old.
Coyotes are less important predators of moose when compared to bears. There is little evidence that coyotes hunt and kill moose, though it is possible that young calves or sick individuals are occasionally attacked.
Coyotes and bears alike will consume moose carcasses opportunistically, and moose that have died from other causes are an important source of food for these animals throughout the year. Besides bear and coyote, moose carcasses provide food for a variety of scavengers in the Acadian forest, including foxes, vultures, crows, marten, and fisher, to name a few.
Defining a 'healthy' moose population
Since moose play an important role in the ecosystem as both consumers and as food for other animals, it's important for us to maintain a healthy population of moose in the Fundy Biosphere Reserve. But what does that mean? How do we decide what a healthy population looks like? Like most good questions, the answer is complicated! There is no magic number; instead, the 'right' number of moose depends on achieving a balance between the biological needs of the population, and our own interests. Since our interests are varied (and sometimes conflicting), and the biological needs of moose populations are poorly understood, defining what a 'healthy' population means is surprisingly difficult.
To start, it is helpful to ask a question: how many moose do we want? In Southern New Brunswick, we want enough moose to ensure that our children and our children's children will know the thrill of spotting a moose neck deep in a lake. We want enough moose so that hunters can enjoy their sport, and so that moose remain a Canadian cultural icon. On the other hand, we don't want so many moose that they pose a threat to our safety on the roads, or that they reduce the amount of habitat available to other species. Maintaining a healthy moose population is a real balancing act!
New Brunswick does not have a target density estimate for its moose population. In other provinces like Ontario4, an 'ideal' moose density is calculated between 0.2-0.4 moose/km2. We can use this estimate to guide our management decisions, at least until we generate our own targeted density.
Moose populations in New Brunswick and the Fundy Biosphere
Currently, the Department of Natural Resources (DNR) estimates that there are ~30,000 moose in New Brunswick5. This number represents our 'best guess' and is not a true count of the population. In other words, nobody has gone out into the all the woods and bogs in New Brunswick and counted heads.
The DNR gets their information primarily from hunters, and the number of moose that they shoot each year. From this data, we can speculate whether the population is increasing or decreasing. The annual moose harvest is set at about 12% of the moose population each year, and therefore the exact number of licenses sold changes each year, based on the previous year's harvest. In order to better manage moose populations throughout their New Brunswick range, the province is divided up into 25 'Wildlife Management Zones' (WMZs). This system allows the DNR to respond to changes in moose populations that may be localized within one region of the province. The primary management tool used by the DNR to respond to changes in the moose population is the annual moose harvest quota.c
In some WMZs, it is thought that there are too few moose. Symptoms of too few moose in the population include: declining hunter success, declining age of the moose harvested, and an increasing ratio of cows to bulls harvested. The DNR's response to these changes may be to decrease the number of licences sold in the affected areas, or to close the hunting season completely. For example, WMZs 18 and 24 were closed from 1990-1993 before being reopened, while zones 26 and 27 have never been open for moose hunting since the implementation of the WMZ system (5). There are just too few moose to support a recreational hunt in these areas.
In other zones, there are thought to be too many moose. When the number of car-moose collisions increases, or when moose begin to impose on farm land and crops, the DNR can increase the number of licences in a specific WMZ, to manage for an overabundance of moose. This year for example, in 8 WMZs across the province including those within the Fundy Biosphere, the moose quota has been raised from a 12% harvest rate to 16%, in an attempt to reduce the number of moose-vehicle collisions. A 16% harvest rate is predicted to stop the moose population from increasing in these areas, without causing a population decline.
Factors that affect moose populations in the Fundy Biosphere
There are several causes of moose mortality that are important determinants of the overall size and health of the population. Since we don't know the exact number of moose in the province, it is difficult to speculate how many moose are killed each year by any one of these factors. The following is a list of factors that limit moose populations, in order of relative importance:
Hunting: regulated + unregulated
Regulated hunting is the only source of moose mortality for which we have an accurate estimate of the number of moose killed. Each year, about 12% of the moose population in New Brunswick is allocated to the regulated hunt5. Taken alone, this regulated hunt is not considered to be a significant contributor to moose mortality; however, the sum of all hunted animals (which includes those harvested by DNR regulated hunters, Aboriginal hunters, and poachers) is probably the most significant source of moose mortality in the province.
Interactions with white tail deer
While competition for resources between deer and moose may occur, the primary concern over moose-deer interactions is the transmission of a parasitic nematode Parelaphostrongylus tenuis (7). The 'brain worm' as it is called, lives without symptom in its native host the deer; when transmitted to moose, P. tenuis causes a variety of symptoms that eventually lead to death. Since upwards of 90% of deer are thought to carry the parasite, there is a high potential for moose to acquire it in areas where moose and deer distributions overlap. Current research at the University of New Brunswick is attempting to quantify moose mortality due to P. tenuis in our region.
Predation by bear
It is speculated that predation of new born calves by black bears may be an important factor limiting juvenile moose survival. Depending on location, between 10-80% of black bears in this province consume moose calves as a part of their diet. Since we do not have an accurate estimate of the number of bears in the province, it is difficult to speculate exactly how many moose calves are predated each year.
Despite our best efforts, 400-500 moose are reported killed by vehicle collision each year (6). Though the continued use of highway fencing is thought to have reduced the number of vehicle collisions with moose in some regions, there continue to be a high number of collisions. In addition, only moose that die on the road are recorded; thus moose that are struck and wonder off into the woods before dying are not included in this estimate. In some areas where the number of moose collisions is high, hunting quotas have been increased in hopes of reducing these events.
Habitat loss and fragmentation
The effect of habitat change through industrial forestry on moose populations is complex. On one hand, wide spread clear-cutting practises have created ideal foraging habitat for moose; forest regeneration after clear cutting provides moose with access to large quantities of their favorite leafy browse. On the other hand, moose require large tracts of closed canopy forest, to keep cool in the summer, and for shelter in the winter. A reduction in old-age forests is thought to have contributed to the decline of moose in mainland Nova Scotia (7). Our industrial forestry practises can indirectly effect moose populations as well, both by increasing human access to moose, and by increasing the frequency of moose-deer interactions. The direction and magnitude of forestry effects on moose populations are largely unknown.
Collaborative aerial moose surveys in the Fundy Biosphere
If it seems like the answer to most moose-related questions is "we don't know", you're right! Despite our love of moose, there are many basic questions that remain unanswered. The Fundy Biosphere Reserve is trying to answer at least one good question: how many moose are in the Fundy Biosphere region? Since aerial surveys were last conducted by DNR in our region in 1995, there is a need for a current, up-to-date estimate.
Working together with the Maritime College of Forest Technology8, Fundy National Park9, and with funding through the New Brunswick Wildlife Trust Fund10, we have been conducting aerial moose surveys within and around Fundy National Park. These surveys are important for several reasons: they will help us to generate accurate moose density data; they will allow us to test and refine protocol for future aerial moose surveys; and they help to build the research and communication capacity of our future biologists and resource managers. This year (2012-2013) will be our third and final year of aerial moose surveying, and we are eager to get back up in the air this winter.
Through our aerial surveys, we estimate the moose density in and around Fundy National Park to be approximately 0.174 moose/km2. Given that a 'healthy' population density is around 0.2-0.4 individuals/km2, this estimate might seem a little low; especially since National Parks are supposed to provide protection to wildlife and their habitat. Does this mean that our moose population is unhealthy? In short, no! There are several factors that are important for the interpretation of this density estimate.
First, since logging activities are prohibited in Fundy National Park, and forest fires have been suppressed for over 60 years, much of the Park is mature forest cover. Mature forest cover provides moose with essential habitat for thermoregulation in both the summer and winter months (7); however, it does not provide the quantity of young, regenerating forage necessary to feed high densities of moose. Given the Park's close proximity to large, industrial clear cuts, it is likely that moose use the Park as a sort of home base: they feed in nearby clear cuts, but return to the dense, old-growth forest when needed. Thus on any given day, the moose density in the Park may be low, but its importance or value as a refuge for the Fundy biosphere's moose population cannot be underestimated. In fact, access to large tracts of mature wilderness like Fundy National Park may be one of the differences between the health of Nova Scotia's and New Brunswick's moose populations.
The future of moose
The future of moose in the Fundy biosphere depends on the balance that we strike between our own interests, and the biological (e.g. habitat) needs of the moose population. If we collectively decide that moose are important to us, for their value as a game species, a provincial icon, or simply because we like having them around, then the future of moose looks bright. Public interest fuels political interests in funding research and preserving habitat. By staying informed and by engaging younger generations, we are ensuring the future of our moose.
For more information
1. Ontario Ministry of Natural Resources. 2009. Moose Biology. Ministry of Natural Resources, Wildlife Management. http://www.mnr.gov.on.ca/en/Business/FW/2ColumnSubPage/STDPROD_090559.html
2. Parker, G. 2003. Status report on the Eastern Moose (Alces alces americana Clinton) in Mainland Nova Scotia. Report prepared for the Nova Scotia Department of Natural Resources, Halifax, Nova Scotia, Canada.
3. Risenhoover, K.L., Maas, S.A. 1987. The influence of moose on the composition and structure of Ilse Royale forests. Canadian Journal of Forest Research, 17(5): 357-364.
4. Ontario Ministry of Natural Resources. 2009. Moose Population Objectives Setting Guidelines. http://www.mnr.gov.on.ca/stdprodconsume/groups/lr/@mnr/@fw/documents/document/263993.pdf
5. New Brunswick Department of Natural Resources. Big Game Harvest Reports 2011. New Brunswick Department of Natural Resources, Fish and Wildlife Branch, Fredericton, New Brunswick, Canada.
6. Think Moose. 2011. New Brunswick Department of Transportation and Infrastructure. www.gnb.ca/0113/moose/think-moose-e.asp
7. Nova Scotia Department of Natural Resrouces. 2007. Recovery Plan for Moose (Alces alces Americana) in Mainland Nova Scotia
8. Maritime College of Forest Technology. 2012. www.mcft.ca/en
9. Fundy National Park. 2012. www.pc.gc.ca/eng/pn-np/fundy/index.aspx
10. New Brunswick Wildlife Trust Fund. 2012. www.nbwtf.ca/eindex.asp