Chapter 1: Mammoth Steppe

Some of the world’s leading mammoth experts say: This mammoth steppe is still growing in the dryer parts of Yakutia, Northeast Siberia. This Yakutian azonal dry steppe is the closest analog to the "periglacial steppe-tundra" or "mammoth-steppe". This azonal dry steppe is growing now in the Sartan River Valley and at Tyubelyakh. - How much fodder is growing there now? In what kind of a climate is it growing up there? Could it feed herds of elephants?

South Yakutia’s Azonal Steppe

The closest modern analog to the periglacial steppe-tundra or mammoth steppe, some experts say, is the steppe growing now in southern Yakutia. It is growing near the Cold-Pole of the Northern Hemisphere. It has many cloudless, warm sunny summer-days, and it is very dry. But there is an important difference: The mammoth steppe was a zonal steppe. It was growing everywhere, stretching from Western Europe across northern Siberia to Alaska, Canada’s Yukon and Northwest Territories, east of the Mackenzie River. The south Yakutian azonal steppe is growing now only at a few favorable spots: in warm, dry basins, and on well-drained, south-facing slopes. The rest of southern Yakutia is covered with larch forest, known there as the "light taiga", in contrast to the "dark taiga", made up of spruce trees.

How much fodder is growing now in this south Yakutian azonal steppe per year? Could it support an elephant or herds of elephants? The late Pleistocene periglacial steppe-tundra was very dry. And the dead grass on this dry steppe is only dry straw. Such dry straw contains only about 2.8% crude protein (dry wt). This dry straw is supposed to have been the only food during the long months of the arctic winter for the mammoth, rhino, bison and horse. Let us look now briefly at two places in southern Yakutia, were azonal steppe is growing now: in the Sartan River valley, south of Verkhoyansk, at the Arctic Circle, and near the village of Tyubelyakh, north of 65°N at the Indigirka River. Dr. B. Yurtsev (1981, 1982) of the Botanical Institute in Leningrad (now St. Petersburg) has studied both of them.

Azonal Dry Steppe: Sartan River Valley

How much fodder is growing now in the Sartan River valley, south of Verkhoyansk, at the Arctic Circle?

The vegetation at the southern slope of the Sartan River valley begins to grow in May. In flat areas and on northern slopes it will begin to grow later. In July the green aboveground biomass in the grass-steppe of the Sartan River valley has reached up to 122 gram per square meter (wet weight). The steppe on the mountain slopes in the valley of the Sartan River valley, south of Verkhoyansk, has a green biomass (wet weight) in July of up to 75 g/m². – How much aboveground dry matter is that? Could an elephant live there?

I asked Heinrich Walter, Professor emeritus at the Botanical Institute of the University of Stuttgart-Hohenheim. He explained to me: The green aboveground biomass of the dry steppe contains about 50% water. In Europe, where it is moister, the meadow grass contains about 70% water. The water-content of the green grass biomass varies somewhat with the time of the day, and with the time of the growing season. 50% dry matter of the aboveground green biomass in the dry steppe would be a good average. – How much aboveground dry matter is growing then in the azonal dry steppe of the Sartan River valley, south of Verkhoyansk?

If the aboveground green biomass in the grass-steppe of the Sartan River valley in July has reached 122 g/m² (wet weight), and if it contains 50% water, about 61 g/m² aboveground dry matter has grown there up to July. The azonal steppe on the mountain slopes of the Sartan River valley, with its aboveground green biomass of up to 75 g/m², would have then about 38 g/m² aboveground dry matter. At the end of July, when the summer drought begins, the grasses turn yellow. They do begin to grow again in the middle of August. Around the 1^st of September, the growing season of the plants then ends. The temperature of the days is falling then below 5°C. This means: After the summer drought, the plants would have only about two more weeks to grow.

According to Boris Yurtsev (1981:22, 23) there are 69 days per year without frost in Verkhoyansk, at the mouth of the Sartan River. Hence, there are at least 296 days of the year, were no green fodder is growing. The mean July temperature at Verkhoyansk is 12.8°C. The January temperature is –48.9°C. The temperature sum of days above 10°C is there 1084°. In the tundra, north of the Siberian treeline, it is less than 300°. Annual precipitation at Verkhoyansk is 153.8 mm. 27.3% of it falls in winter as snow.

At the southern part of the Yana River, at the mouth of the Sartan and the Dugulakh River, near the Arctic Circle, the growing season of the plants (with days above 5°C) is only 60-90 days per year. More than 270 days are below the freezing point. The snow cover remains 200-240 days, according to the Russian Climate Atlas (1972).

Thus, the mammoth would have been able to graze there fresh, green grass for only 60-90 days of the year. If we include the 2 months long summer drought, where the plants are also dry (but some of the herbs remain green), only about 30 days with fresh green grass per year are left. During the other 300-335 days of the year, the mammoth would have had to live then on dry brown grass, high in fiber and low in protein. And of the fresh green grass growing during 30 days of the year, (61-75 g DM/m²) there is far too little. The mammoth would starve to death on the azonal dry steppe of the Sartan River valley also in summer.

Azonal Dry Steppe at Tyubelyakh

Boris Yurtsev (1981) reports that near the village of Tyubelyakh at the Indigirka River arctic steppe is also growing. Where is that? How much fodder is growing there? Could the elephant or mammoth live there now?

The village Tyubelyakh lies at the Indigirka, north of 65°N, north of Nera and south of Ust Moma. The steppe on the flatter ground covers about 60% of the surface. It produces 20 g/m² aboveground dry matter per year. On the mountain slopes near the village of Tyubelyakh, the arctic steppe covers also 60% of the ground. It produces about 40 g/m² aboveground dry matter per year. –In what kind of a climate is this azonal dry steppe growing now at the Indigirka River in Northeast Yakutia?

According to B. Yurtsev (1981:22, 23; 1982:164), Nera, south of Tyubelyakh, near 64°N and 144°E, has a mean January temperature of –48.9°C, and a mean July temperature of 15.3°C. The temperature sum of days above 10°C at Nera is 1016°. Frost-free are 53 days of the year. Annual precipitation is 224.3 mm. 21.4% of it falls as snow.

Ust Moma, north of the village of Tyubelyakh, at the Arctic Circle near 143°E, has a mean January air temperature of –46.9°C and a mean July temperature of 15.0°C. The temperature sum of days above 10°C is 1088°. There are 50 frost-free days per year. Annual precipitation at Ust Moma is 190 mm. There are 60-90 days with an average temperature above 5°C.

In other words: the growing season of the plants up there is only 60-90 days long. 240-270 days of the year have an average temperature of below 0°C, the freezing point of water. The snow covers the ground 200-240 days of the year, according to the Russian Climate Atlas (1972). In such a climate and on such a plant-cover, the woolly mammoth would have starved to death, due to lack of protein and energy, within a few months or weeks.

Central Asia’s Tundra and Steppe

Adapted from H. Walter (1974) pp. 240, 246. The 10°C temperature sum for the arctic tundra’s southern limit of 300° is from the Russian Climate Atlas (1972) map 27. From this I have taken 275° as an average for the arctic tundra. Central Asia’s forest-steppe has a temperature sum with days above 10°C of 2100-2150°, or an average 2125°. That is 7.7 times larger than the 10°C.ts of the arctic tundra, with its 275°.

Central Asia’s zonal steppe – south of the forest-steppe -, has a temperature sum with days above 10°C of 2200-2350°, or an average of 2275°. That is 8.3 times more than that of the arctic tundra. Central Asia’s dry steppe has a temperature with days above 10°C of 2300°. That is 8.4 times more than that of the arctic tundra.

Arctic tundra and zonal steppe are growing in two entirely different types of climate. One cannot have a zonal steppe in the climate of the arctic tundra. This shows us, in which climate the mammoth steppe of the Far North has grown. It had to have a temperature sum with days above 10°C of 2200-2350°, or an average 2275°. That is 8.3 times warmer, than the climate, in which arctic tundra is growing. This zonal mammoth steppe is only able to grow in a temperate climate. It cannot grow in an arctic climate.

The elephant is still able to live now, where 250 g DM/m² has grown per year (month by month). That is marginal elephant habitat. The tusker will starve to death with a full stomach, where only 200 g DM/m.² has grown per year (Phillipson, J. 1975).

The subarctic azonal dry loess-steppe in the southern Yukon (near 62°N on Sheep Mountain, Kluane Lake) produces now at 200 mm precipitation per year about 61.7 g DM/m². That is 0.3085 g DM/m² per 1 mm of precipitation per year. The lowest amount of dry plant-matter, needed to feed the elephant (of 250 g DM/m²) would only be able to grow there now in this subarctic climate, if there were about 810 mm of precipitation per year.

The subarctic azonal steppe in northeastern Yakutia produces now 38-61 g DM/m² per year in the Sartan River Valley, south of Verkhoyansk, at the Arctic Circle, at a mean annual precipitation of 153 mm.

At Tyubelyakh in northeastern Siberia, north of 65°N, at the Indigirka River, 20-40 g DM/m² is growing now at 224.3 mm precipitation per year. On Yakutia’s subarctic azonal steppe, an average 0.23987 g DM/m² per millimeter of precipitation is growing now per year. 250 g DM/m² per year would grow there now, if there were 1042 mm of precipitation per year.

The elephant is still able to live now, where 250 g DM/m² has grown per year (month by month), if this fodder contains enough protein also during the dry season. That is marginal elephant habitat. The tusker will starve to death with a full stomach, where only 200 g DM/m.² has grown per year (Phillipson, J. 1975).

The subarctic azonal dry loess-steppe in the southern Yukon (near 62°N on Sheep Mountain, Kluane Lake) produces now at 200 mm precipitation per year about 61.7 g DM/m². That is 0.3085 g DM/m² per 1 mm of precipitation per year. The lowest amount of dry plant-matter, needed to feed the elephant (of 250 g DM/m²) would only be able to grow there now in this subarctic climate, if there were about 810 mm of precipitation per year.

The subarctic azonal steppe in northeastern Yakutia produces now 38-61 g DM/m² per year in the Sartan River Valley, south of Verkhoyansk, at the Arctic Circle, at a mean annual precipitation of 153 mm.

At Tyubelyakh in northeastern Siberia, north of 65°N, at the Indigirka River, 20-40 g DM/m² is growing now at 224.3 mm precipitation per year. On Yakutia’s subarctic azonal steppe, an average 0.23987 g DM/m² per millimeter of precipitation is growing now per year. 250 g DM/m² per year would grow there now, if there were 1042 mm of precipitation per year.

Upper Pleistocene distribution of the woolly mammoth in Eurasia. From: R.-D. Kahlke (1994) Fig. 13. This elephant has lived then also in northern Siberia, up to the tip of Taimyr Peninsula and further east on the now submerged continental shelf. In an arctic climate this was not possible.

Woolly mammoths grazing on zonal steppe. From: E. Probst (1986:317). The mammoth used to lean the weight of its large head with the lower part of its tusks on the ground, when grazing and when resting. That is why the bottom of the tusks (near the tips) is usually worn down a little. They did not shovel any snow with them. The elephant is still able to live, where 250 g DM/m² has grown per year (month by month). This is marginal elephant habitat. The tusker will starve to death with a full stomach, where only 200 g DM/m² has grown per year (J. Phillipson, 1975).

The subarctic steppe in the southern Yukon Territory (near 62°N, on Sheep Mountain, Kluane Lake) produces now at 200 mm precipitation per year about 61.7 g DM//m². That is 0.3085 g DM/m² at 1 mm precipitation per year. The lowest amount of dry plant matter, needed to feed the elephant (of 250 g DM/m² per year), would only be able to grow now up there at a mean annual precipitation of 810 mm.

The subarctic azonal dry steppe in Northeast Yakutia produces now 38 - 61 g DM/m² in the Sartan River Valley, south of Verkhoyansk, at the Arctic Circle, at a mean annual precipitation of 153 mm. At Tyubelyakh in Northeast Yakutia, north of 65° N, at the Indigirka River, 20 – 40 g DM/m.² is growing at 224.3 mm ppt per year. On Yakutia’s subarctic azonal steppe, an average 0.23987 g DM is growing now per 1 mm of precipitation per year. 250 g DM/m² per year would be able to grow there now at 1042 mm precipitation per year. This proves quantitatively that the mammoth would not be able to live up there in an arctic or subarctic climate.