HKHPE 19 03

In the southwestern Northwest Territories of Canada, the rare wood bison (Bison athabascae) is still living. How much food is growing there? How is it able to survive the long cold winter? What have scientists found now out about this?

We read about this in the "Status report on Wood Bison (Bison bison athabascae) in Canada, 1987", by The Wood Bison Recovery Team, December 1987 by C. Gates et al. 1987: In August 1963, 18 wood bison (six males and 12 females) were transplanted from WBNP (Wood Bison National Park) to the MBS (Mackenzie Bison Sanctuary) on the west shore of Great Slave Lake, NWT. The population grew to more than 1200 bison after calving in 1984. During April 1987, 1718 bison were counted (C. Gates. pers. comm.). The population has shown a consistently high rate of growth since it was introduced.

The carrying capacity of the entire range is not known, but continued expansion into other suitable habitat is expected. In 1987, bison were seen near Fort Providence and at Mills Lake. A habitat evaluation program was conducted in the MBS, to determine range composition and biomass of available forage. The results of the habitat research indicated, that a population of 7100 wood bison could be supported in the MBS, based on available forage and assuming an even grazing pressure throughout the various meadow habitats (Government of the Northwest Territories 1987). - Gates, C. et al. (1987:29, 30)

In addition to the typical cover types of the boreal forest, there are large wet and mesic (= with medium moisture) meadows, associated with shallow depressions. These depressions are relict lake beds, with well-defined shorelines, that typically contain only small areas of water, after spring runoff. Sedge and grass communities, that surround water bodies, can yield up to 5800 kg/ha (580 g/m²) dry matter of herbage standing crop late in the growing season (Mychasiw 1987). - Gates, C. et al. (1987:36)

During spring and early summer, wood bison most often forage in mesic meadows, where dominant herbaceous species are reedgrasses (Calamagrostis spp.), wheatgrass (Agropyron trachycaulum), foxtail barley (Hordeum jubatum), and slough sedge (Carex atherodes). Several species of willow (Salix spp.) and, to a lesser extent poplars (Populus spp.) are the dominant shrubs in the habitat. In wet meadows, dominant plant species are slough sedge and water sedge (Carex aquatilis). Use of wet meadows during summer coincides with hot weather and may be related to seeking cool environs as much as foraging behaviour. Later in summer, wood bison disperse into small groups and occupy coniferous and mixed-wood forests. This change in habitat selection coincides with the rut, which lasts from mid July to October in the MBS. During the rut, wood bison are rarely seen in open areas.

After the ground has frozen, usually in November, wood bison in the MBS shift to open habitats, particularly wet meadows. Large aggregations are typically present in these habitats throughout the winter, although weather may influence daily use patterns. Wood bison continue, to use wet meadows, until spring runoff water accumulates and the soil thaws. - Gates, C. et al. (1987:36, 37)

Aboveground plant production (gDM/m² yr) dry weight in the Fort Providence area (where wood bison of the Mackenzie Bison Sanctuary are also living now).

Bailey, A. and D. Penner, 1973. The potential of rangelands in the Fort Providence, N.W.T. area to support muskox: An interim report on research results, 1973. Unpubl.Rept. Gov’t. of N.W.T. Contract No. 73-1-252: Wet sedge meadows in the Fort Providence area (2533 kg/ha) (253.3 g/m²). Bailey and Penner (1973). Bailey and Penner (1973) noted approximately a 50% decrease in wet sedge meadow yield in 1973, compared to 1972, which shows the high variability, associated with vegetation production.

Dry sedge meadow production (1760 kg/ha) (176.0 g/m²) at Fort Providence (Bailey and Penner 1973).

Willow shrub community (2130 kg/ha) (213.0 g/m²) at Fort Providence (Bailey and Penner 1973).

Mature aspen forest (728 kg/ha) (72.8 g/m²) near Fort Providence. In H. W. Reynolds et al. (1980:22, 23).

We shall find out more in the following report: "Diet and habitat selection of wood bison in relation to seasonal changes in forage quantity and quality", by Nicholas C. Larter, Department of Zoology, University of British Columbia, Vancouver, B.C., Canada, and Cormack C. Gates, Department of Renewable Resources, Government of the Northwest Territories, Fort Smith, N.W.T., Canada:

The Mackenzie Bison Sanctuary covers an area exceeding 6200 km² on the western side of Great Slave Lake (61°30´N, 117°00´W) in the Northwest Territories. It is located in the Upper Mackenzie Section of the Boreal Forest Region (Rowe 1972), in the emerged bed of a once vast glacial lake. Glacial action has resulted in a nearly level, but undulating topography. Postglacial isostatic uplift has lowered the water table and dried the shallow lake beds in the area. These lakes are gradually filling in with sedges and grasses, while woody plants, notably willows (Salix spp.) are invading the lake margins. Three main open habitat types, associated with the shallow lake beds, were identified in this study (i) wet sedge meadow (WSM), (ii) willow savanna (WS), and (iii) sparsely vegetated rocky marl (ML).

WSM is found, where there is year-round standing water. It contained high-biomass stands of sedge, dominated by Carex atherodes (slough sedge) and Carex aquatilis (water sedge). The WS habitat is located in more mesic areas, often bordering WSM. Larter, N. et al. (1991:2677). Fig. 1. The Mackenzie Bison Sanctuary, N.W.T., Canada. Current bison range (in 1991): Northern limit of range: about 62.2°N, north and west of Great Slave Lake..

Plant sampling was conducted between 1 June and 15 October 1987, Larter, N. et al. (1991:2678). Crude protein = N x 6.25. Eleven adult female and 8 adult male wood bison were chemically immobilized and radio-collared between February 1986 and July 1987.

Diet selection. During winter, the diet was dominated by sedge (96.1-98.8%), whereas in summer, it became a more diverse mixture of sedges, grasses, and shrubs. The fall diet was the most diverse, with lichen becoming a major component (34.3-40.6%). - Larter, N. et al. (1991:2679)

Forage quality. In all habitats, all forages, except lichen, showed a significant linear decrease in percent nitrogen concentration between June and October. Lichen showed a consistently low percent nitrogen concentration throughout the sampling period. ... Available crude protein increased to a midsummer (July 15) peak and then declined (Fig. 5a). WS (willow savanna) provided the most available crude protein throughout the sampling period. - Larter, N. et al. (1991:2679)

Forage quantity. Generally, green biomass increased until mid-July, remained steady until mid-August, and decreased rapidly in September. Dead current year’s growth first appeared during the July 30 sampling period. This trend was seen in all habitats. WSM (wet sedge meadow) produced the most green biomass: five times that of WS (willow savanna) (Fig. 5b). However, the muddy substrate of WSM precludes foraging by bison during ice-free periods of the year. ... Prior to the onset of winter, WSM provided the greatest standing crop (186.6 g/m² dry weight) of forage). - Larter, N. et al. (1991:2680)

The diet of wood bison in the Mackenzie Bison Sanctuary was more diverse, than the almost exclusive grass or grass and sedge diet of plains bison or of bison, inhabiting Wood Buffalo National Park and vicinity. ... Plains bison, inhabiting riparian willow communities, used browse (Waggoner and Hinkes 1986). However, bison in the Slave River lowlands, an area with vegetation, similar to that of the Mackenzie Bison Sanctuary, used little browse and no lichen (Reynolds et al. 1978). Summer browsing by wood bison was similar to that of European bison (Bison bonasus), which included up to 33% browse in their summer diet (Browski and Kossak 1972).

The diet (of the wood bison in MBS) was most diverse in early summer and fall, but consisted almost exclusively of sedge in winter. This pattern might be expected, because in early summer, all forages are high in nitrogen and low in fibre and provide an abundance of high-quality forage, to choose from. In fall, forages contained low nitrogen and high fibre levels and the preferred sedges had been heavily grazed, forcing the animals, to take, what forage was available. In winter, frozen WSM provided extensive stands of previously ungrazed sedge. Bison, being large bulk feeders, can process large amounts of low-quality forage. The winter diet was similar to that, found in other bison studies. - Larter, N. et al. (1991:2681, 83)

Decreased amounts of surface water in 1987 reduced the standing crop of all forages, especially sedges in WS (willow savanna), the preferred summer foraging habitat. The lower proportion of sedge in the diet during 1987 was offset by higher amounts of grass and willow, indicating the capability of wood bison, to switch from a diet high in sedge, when sedge biomass is scarce. However, a diet high in lignin, like willow, may not be advantageous. Bison have a large rumen and a relatively slow turnover rate. (= Its food stays a long time in its digestive tract). - Larter, N. et al. (1991:2683) .

Slough sedge was of superior quality to water sedge during both summer and winter. Grasses had the highest nitrogen content, but slough sedge had the lowest fibre concentration of the three forages. New grass growth is associated with clumps of the previous year’s dead material, whereas sedge growth is not. Because the bison’s large mouth restricts the selection of individual stems (Hanley 1982), both current growth and dead material would be ingested, when bison forage on grass. This would negatively affect forage quality, by lowering the nitrogen level and raising the fibre concentration of the ingested forage. - Larter, N. et al. (1991:2683). By 24 September, all forages had crude protein levels below 5.9%, the marginal level, at which maintenance requirements for beef cattle are met (National Academy of Sciences-National Research Council 1976). - Larter, N. et al. (1991:2683)

During fall, bison move into forested habitats. Lichen was a major constituent of the fall diet and was only found in forested habitats. CNBG (wet coniferous forest) provided the greatest lichen biomass of all habitats. The majority of relocations of radio-collared bison during fall were in these habitats.

Habitat selection. During both summer and winter, wood bison selected habitats, that provided the most available crude protein. In fall, forage quantity and quality became more homogeneous throughout the habitats. Bison dispersed amongst all habitats. Forested habitats were used heavily, especially the coniferous habitat, which supplied the greatest biomass of lichen. Larter, N. et al. (1991:2683)

Wood bison cow on a sedge meadow in the southwestern Yukon Territory. From: Eric Fairclough, Minister of Renewable Resources, Yukon Bison Management Plan 1998 to 2003 p. 7.

The Mackenzie Bison Sanctuary lies west of Great Slave Lake, NWT (61°30´N, 117°00W). How many wood bison is the Mackenzie Bison Sanctuary able to support, if they grazed evenly? How much wood bison biomass would the Mackenzie Bison Sanctuary then be able to support?

During the time, when large herds of steppe bison, steppe horses, and woolly mammoths were grazing in northern Canada and Alaska, also the lion was hunting up there. That is, residential lions, with their own home range, raising cubs, were living then in the Far North. Would also the lion be able, to live now in the Mackenzie Bison Sanctuary, if 7100 wood bison were grazing there?

Scientists have found out: Up to about 7100 wood bison would be able, to live in the Mackenzie Bison Sanctuary, if they spread out evenly. That is, if the grazing pressure were even. Gates, C.C. et al. (1987:28-30). The whole MBS is at least 6200 km² large.

In winter, when the ground is frozen, the wood bison in the Mackenzie Bison Sanctuary is grazing on the wet sedge meadow. The ground is covered there with a shallow layer of water. The dominant plant there is the sedge Carex atherodes. In summer, the wood bison is living on the willow savanna. That is usually next to the wet sedge meadow. There the ground is dry.

In autumn, the wood bison at the MBS leaves the open area, the willow savanna and wanders into the coniferous forest. There it is also grazing the lichen. In August, about 20% of their diet is made up of lichen, in September 30%, and in October 55%. Because in the dense spruce forest, there is not enough grass or sedge, to feed those large animals. From July till October, the wood bison is there in the rutting season. And during this time, they are hidden in the dense spruce forests. Let us assume first, that the 7100 wood bison (which are able to live up there) were using the whole area of the MBS, of about 6200 km². How many bison and how much bison biomass would there be then per square kilometer?

7100 bison : 6200 km² = 1.145 bison. The average body weight of the bison in the Slave River Lowland, south of Great Slave Lake, is 400 kg. According to other experts, the average body weight of the bison is 450 kg.

458-515 kg/km² hoofed mammal biomass is not able to feed the lion. This means: Not even the nomadic lion, not raising cubs, would be able to live there. Would the lion be able to live in the Mackenzie Bison Sanctuary, if we take now only the open area? 61.9% of this 6200 km² large wood bison sanctuary is covered by dry coniferous forest (spruce forest). There is little or no grazing pasture. The remaining 38.1% of open country are covered by mixed deciduous-coniferous forest, willow-aspen, willow-savanna, and wet sedge meadow.

This means: When using only the open area (38.1%), of the MBS, without the dense spruce forest, there could live then up to 3.0 bison/km². That is a bison biomass of up to 1200-1350 kg/km² At this hoofed mammal biomass of 1200-1350 kg/km², the nomadic lion would be able to live. Because he has no own home range, and is able to follow the herds. But the nomadic lion (and tiger) does not raise any cubs, even when living there for many years. There is too little food. So, no lion population would be able, to survive up there. When no new cubs are growing up, the nomadic lion will die off within a few years, due to old age.

The bison herd, expanding into a new area, may be able to increase by 15-20 per cent per year. That is, until it has reached the full carrying capacity of its home range. Then the population might crash. The lion, tiger and other large cats take about 9-10% of the large mammal biomass per year.

The average adult male lion, weighing 170 kg, needs 2555 kg meat/year. 33% of the prey is inedible. So he must kill 3813 kg ungulate prey/year. The average adult lioness, 120 kg, needs 5 kg meat/day, and 1825 kg meat/year. She must kill then 7.463 kg prey/day, and 2723 kg/year. - Schaller, G. (1972).

How much food does a lion, the lioness and their two cubs, 6 months old, need on their 18 km² home range per year? The adult male lion (170 kg BW), the lioness (120 kg BW), and 2 cubs, 6 months old, weighing 20 kg each: how much food do they need per year? And how large must be the ungulate biomass?

The whole lion family must kill at least 5095 kg ungulate biomass in one year. That is about 9% of the total prey biomass. This means: There has to be then a prey biomass of hoofed animals of at least 56,611 kg on their 18 km² home range. That is a prey biomass of hoofed animals of 3145 kg/km². That is the lean season prey biomass, during the poorest month of the year. Any surplus during the rest of the year is irrelevant. How many bison are that? 5095 kg/km² : 400 kg/bison = 12.7 bison (average body weight) per year.

This means: The residential lion (or tiger) would not be able to live now on the Mackenzie Bison Sanctuary, even if we assumed, that up to 7100 wood bison were living there on only 38.1% of the of this sanctuary. That is, in the open country, where the bison is able to find enough to eat.

In autumn, from July till October, the wood bison in the MBS is in the rutting season. The herds are leaving then their pastures in the open country (mainly the willow-savanna) and disappear in the dense dark spruce forest. If the residential lion had set up its home range on the open country (bison pasture), or at the edge of the forest, how much food would the lion family have then in fall? How much large mammal prey biomass would it have then in August, September and October?

The answer: In fall, the wood bison is in its rutting season. The herds have disappeared into the dense spruce forest. The lean season prey biomass on the home range of the lion family (in the open country) would be then near zero. The residential lion would not be able, to leave its home range, to follow the herds, like the nomadic lion. Not only the two cubs, but also the adult male lion and the lioness would starve then to death. They would not be able, to live there as residents, because the prey biomass during the poorest month of the year is far too low.

During the summer, the wood bison in the Mackenzie Bison Sanctuary is living mainly on the willow-savanna. That is the dry pasture, usually next to the wet sedge meadow. In winter, the wood bison is grazing up there mainly on the then frozen wet sedge meadow. How much crude protein (dry weight) does the pasture on the Mackenzie Bison Sanctuary contain in summer and in winter?

The grass on the willow-savanna contains at 1 June 24.62% crude protein (dry weight). And at the 15 October only 3.03% CP. The other edible vegetation contains 21.46% CP at 1 June, and 2.65% CP at 15 October.

The sedge Carex atherodes, the slough sedge is the dominant plant on the wet sedge meadows. The sedges make up 96.1-98.8% of the winter diet of the wood bison (Larter and Gates 1991).

How much digestible crude protein (DCP) does the adult bison need, to maintain its body weight? What is the minimum maintenance level of crude protein in the diet? Is it 6-7% crude protein (dry weight)? – Yes, when studying the captive bison in a pen. – Also out on the open range? How much crude protein do large African grazers need per day?

N. Owen-Smith reports in his article "Factors Influencing the Consumption of Plant Products of Large Herbivores" in Ecology of Tropical Savannas (1982:375): African buffalo 850 kg body mass, 2% of live mass per day food intake (dry mass). The minimum maintenance level of crude protein in the diet for a 500 kg African buffalo cow is 5%.

Zebu cattle, 400 kg body mass, eating hay 5% CP. Digests 49% of dry matter. Food intake (dry mass) as % of live mass per day 1.6%.

Wildebeest 160 kg body mass, hay 5% CP, digests 64% of dry matter. 2,1 % of live mass per day food intake (dry mass).

Oryx 219 kg body mass, hay 5% CP, digests 61% of dry matter. Takes in food (dry mass) 2.2% of live mass per day. - Owen-Smith, N. (1982:380) Table 8

The maintenance energy requirements of free-ranging animals may be considerably greater, than indicated by experiments on penned animals. Ledger (1977) found that 450 kg steers, which walked 15 km per day, required 97% more food, than would have been the case, if they had been kept inactive in pens.

A certain amount of dietary protein is inevitably lost as ‘metabolic faecal nitrogen’, comprising chiefly the bodies of microorganisms, developing in the large intestine from cells, sloughed off from the digestive tract lining, digestive enzymes, and remaining food residues (Hungate 1975). For domestic stock, metabolic faecal nitrogen amounts to about 5.6 g N per kg dry matter of wood ingested (Waldo 1968). (That is 3.5% crude protein, dry weight). Only nitrogen above this threshold level in the food is available to a large herbivore for its own metabolic needs.

Ruminants also possess the ability, to recycle surplus ammonia back into the rumen via the bloodstream or saliva as urea, with an increasing proportion being recycled, rather than excreted as the nitrogen content of the diet declines (Livingston et al 1962). Cattle and deer apparently recycle a greater proportion of plasma urea, than do sheep. Muscle tissue may also be catabolized (= broken down), to produce urea for cycling to the rumen under sub-maintenance conditions, and this could be important in maintaining bacterial and protozoal populations. - Owen-Smith, N. (1982:383, 384)

Reproductive condition has a great effect on nutritional requirements. During peak lactation, the protein and energy requirements of female mammals may be 60% and 40% greater, respectively, than those of reproductively inactive animals. Nutrient demands rise markedly during the last third of pregnancy. ... The stomach fills of lactating elephant cows were 20% higher, than those of non-lactating females (Malpas 1977). (1982:384)

The quantity of vegetation, harvested by an individual ungulate, depends both on its foraging efficiency, in terms of the food ingestion rate achieved, and on the proportion of the day, that it devotes to foraging, rather than to other activities. Animals may compensate to some extent for declining food availability by increasing their feeding time, but the range of compensation is limited. ... Cattle increased their feeding time from 9,1 hr day to 10,7 hr day with progressive defoliation of a grass sward, but further compensation was restricted by the bulk of food in the rumen and its slow turnover rate (Chacon and Stobbs 1976).

For non-ruminants, and concentrate selectors among ruminants, this restriction may be less severe. Foraging time allocations tend to increase with increasing body mass, suggesting, that large species are less efficient at harvesting food in relation to their body size, than smaller species. For example dikdik spend about 31% of the 24-hour day foraging, waterbuck 37%, white rhinos 49%, and African elephants 75%. - Owen-Smith, N. (1982:390)

From this I do conclude: The bison in its wild state, adapted to food, low in protein and high in fiber. It is able, to maintain its body weight, when its food contains at least 5% crude protein (dry weight), not 6 or even 7%. Food, which contains 3.5% crude protein (dry wt) or less, the bison is not able to digest anymore. The bison needs in winter, when it is on winter maintenance, with its reduced metabolic rate, food, which contains at least 3.6% crude protein (dry wt). The additional protein, which the bison needs, but does not get then through its food, it will get from its own muscle tissue. It will loose then 10-15% of its body weight. This emergency protein, taken from its own body, it needs now urgently, to stay alive. It will enable the micro-flora in its digestive tract, to survive and to break down and digest the food, which the bison has eaten. Without this emergency protein, which the ruminant taken from its own body, the micro-flora would starve to death. When the micro-flora is gone, when it has died or when it has become too weak, to digest the food, which the bison has eaten, this will happen: It will not be able, to digest it anymore. The bison will then also starve to death, with a full stomach.

Wood bison grazing on a wet sedge meadow at the shore of a lake, in the southwestern Yukon Territory. The sedge meadows growing in or near water are now the most productive places in the Yukon Territory and Northwest Territories. Without them, the bison probably would not be able to live now up there, because annual aboveground plant production is very low. From: Eric Fairclough, Minister of Renewable Resources, Yukon Bison Management Plan 1998 to 2003 p. 17.

On the willow savanna of the Mackenzie Bison Sanctuary, the slough sedge Carex atherodes contains on 1 June 20.61% CP (dry wt), and on 15 October only 2.778% CP. But in fall, the bison herds have used up most of the feed on the dry willow-savanna. And as long, as the ground is not frozen, they are not able, to graze in the wet sedge meadow, where the sedges are growing in surface water. On 1 June, the wet sedge meadow contains 13.26% CP (dry wt), and on 15 October only 2.399% CP. Larter and Gates (1991:2681) Fig. 4. During the winter months, the crude protein content of the aboveground vegetation up there does not change much. In the last month of winter, in April, it might be still lower.

Would the elephant (or mammoth) be able, to live in the Mackenzie Bison Sanctuary, west of Great Slave Lake, in Canada’s Northwest Territories? Would the elephant be able, to find enough to eat up there during the long subarctic winter, when grazing on the frozen wet sedge meadows, the most fertile pasture?

Charging woolly mammoth. Engraved on an ivory-plate from a mammoth tusk, La Madeleine, Dordogne, S.W. Fance. 29.5 cm wide. After Breuil. From: H.-G. Bandi and J. Maringer, Kunst der Eiszeit (1952) Fig. 9.

Month	%CP dry wt	% CP digested	DCPI g/day	DCPI g/mth	DCPI g/mth needed	DCPI deficit & death kg/mth
Oct	2.399	4	66.796	2071	71,603	69.532
Nov	2.399	4	66.796	2004	69,293	67.289
Dec	2.399	4	66.796	2071	71,603	69.532
Jan	2.399	4	66.796	2071	71,603	69.532
Feb	2.399	4	66.796	1870	64,673	62.803
Mar	2.399	4	66.796	2071	71,603	69.532
Apr	2.399	4	66.796	2071	69,293	67.289

6400-kg male elephant. Dry matter intake 97.28 g DM/kg^0.75and 3.228 g DCP/kg^0.75 day for maintenance. I do assume here, that the elephant is able, to take in as much food (dry matter), as it needs, to maintain its body weight. It will starve to death with a full stomach, when its deficit of digestible crude protein (DCP) has reached 220.021 kg or 3.438% of its body weight. This adult elephant will starve to death on the wet meadow of the Mackenzie Bison Sanctuary, N.W.T. around the 7^th of January, after 3 months and 1 week, counting from the 1st October. At the end of the subarctic winter, the 6.4-ton adult elephant would starve to death a second time, due to lack of digestible crude protein (if this were possible), around the 15^th of April.

Month: The 6.4-ton adult elephant begins, to graze on the wet meadows of the Mackenzie Bison Range in the Northwest Territories, in northern Canada at the 1^st of October. I do assume here, that the elephant is able, to take in as much dry matter, as it needs to maintain its body weight.

%CP dry wt. From the beginning of October till the end of April, the wet meadow (the most fertile pasture of the bison) in the Mackenzie Bison Sanctuary, southern Northwest Territories, contains 2.399% crude protein (dry weight).

% of CP digested. When the food contains 2.399% crude protein (dry weight), the elephant is able, to digest about 4% of this food. During the great drought of 1970/71 in Tsavo East, in Kenya, East Africa, about 5000 elephant starved to death with a full stomach, when their food contained 2% crude protein (dry weight) or more.

DCPI g/day. The 6.4-ton adult elephant takes in then 66.796 gram digestible crude protein (dry weight) per day.

DCPI g/mth. In October the 6.4-ton adult elephant takes in then 2071 gram digestible crude protein (dry weight).

DCPI g/mth needed. But in October the 6.4-ton adult elephant needs 71,603 g digestible crude protein (dry weight), to maintain its body weight.

DCPI deficit & death kg/mth. At the end of October, this elephant has taken in then 69.532 kg digestible crude protein (DCP), dry weight, too little, below maintenance.

During the following months, this deficit of digestible crude protein becomes larger and larger. Around the 7^th of January, after 3 months and 1 week, the adult 6.4-ton elephant will starve to death with a full stomach. That is, when its deficit of digestible crude protein has reached about 3.438 percent of its body weight (wet weight).

This proves quantitatively, that the adult elephant (or adult woolly mammoth) is not able, to live now on the wet sedge meadow of the Mackenzie Bison Sanctuary, in Canada’s southern Northwest Territories. It will starve there to death during the long subarctic winter, due to lack of digestible crude protein.

Month	% CP dry wt	% CP digested	DCPI g/day	DCPI g/mth	DCPI g/mth needed	DCPI deficit & death kg/mth
Oct	2.399	4	16.600	514.606	33,925	33.410
Nov	2.399	4	16.600	498.006	32,830	32.332
Dec	2.399	4	16.600	514.606	33,925	33.410
Jan	2.399	4	16.600	514.606	33,925	33.410
Feb	2.399	4	16.600	464.800	30,642	30.177
Mar	2.399	4	16.600	514.606	33,925	33.410
Apr	2.399	4	16.600	498.006	32,830	32.332

The 1000-kg growing elephant begins to graze at the 1^st of October on the frozen wet sedge meadows of the Mackenzie Bison Sanctuary, west of Great Slave Lake, in Canada’s southern Northwest Territories. I do assume here, that the elephant is able to take in as much dry matter, as it needs, to maintain its body weight and to grow. This young growing elephant needs 6.154 g DCP/kg^0.75 (12-15% CP = average 13.5% CP) and 97.28 g DM/kg^0.75 per day.

This 1-ton growing elephant will starve to death with a full stomach, when its deficit of digestible crude protein (DCP) has reached 106.311 kg or 10.631% of its body weight. It will starve to death with a full stomach around the 8th of January, after 3 months and 8 days, counting from the 1^st of October. The 1-ton growing elephant will starve to death a second time, due to lack of digestible crude protein, at the 15^th of April, if this were possible. This proves quantitatively, that the growing 1000-kg elephant is not even able, to live now on the most fertile pastures of the southern part of Canada’s Northwest Territories. It will starve there to death during the long subarctic winter, due to lack of digestible crude protein.

Month	% CP dry wt	% CP digested	DCPI g/day	DCPI g/mth	DCPI g/mth needed	DCPI deficit & death kg/mth
Oct	2.399	4	9.870	305.987	20,172	19.866
Nov	2.399	4	9.870	296.116	19,521	19.225
Dec	2.399	4	9.870	305.987	20,172	19.866
Jan	2.399	4	9.870	305.987	20,172	19.866
Feb	2.399	4	9.870	267.375	18,220	15.214
Mar	2.399	4	9.870	305.987	20,172	19.866
Apr	2.399	4	9.870	296.116	19,521	19.255

The 500-kg weaned elephant calf is grazing here on the frozen wet meadows in the Mackenzie Bison Sanctuary, west of Great Slave Lake, in the southern Northwest Territories. It needs 6.154 g DCP/kg^0.75 (12-15% CP = av. 13.5% CP) and 97.28 g DM/kg^0.75 per day, to maintain its body weight and to grow. The 500-kg weaned elephant calf will starve to death with a full stomach, when its deficit of digestible crude protein has reached 63.215 kg or 12.643% of its body weight. The 500-kg elephant calf will starve there to death with a full stomach, due to lack of digestible crude protein, around the 7^th of January. That is after 3 months and 1 week, counting from the 1st of October. And it would (if this were possible), starve there a second time to death around the 17^th of April. We should also remember here: The young weaned elephant calf will starve already to death, when eating food, which contains only 5.5% crude protein (dry weight).

This proves quantitatively, that also the young, weaned elephant calf (and mammoth calf) would not be able, to live now in northern Canada, in the southern part of the Northwest Territories. That is, at the most fertile spots, in a subarctic climate. There its food contains far too little digestible crude protein during the long subarctic winter, to support an elephant, not to mention, whole herds of elephants.