Bragin Е.А., Bragina Т.М., Ruleva М.М., Demessenov Б.М., Ilyashenko М.А. The status and dynamics of populations of the Great Bustard (Otis tarda) and the Little Bustard (Otis tetrax) in Kostanai Region

1Kostanay State Pedagogical Institute, Kazakhstan, Kostanay 2Southern Federal University, Rostovon-Don, Russia

Abstract

The Great Bustard and the Little Bustard are emblematic species of Kazakh steppes. Populations of these birds were numerous in the middle of the
last century but in the early 1970’s they fare on the brink of extinction. This
paper is based on a long-term observation in Naurzum Reserve and adjacent
territories in 1977-2014 and on territory of Kostanai Region in 1998-2014,
as well as literature data. The paper provides information on the population
dynamics of the Great Bustard and the Little Bustard in Kostanai region, the
factors influenced on decline in their numbers, and the current state of their
populations. Population dynamics of Little Bustard during the end of 1990th
and until 2010 characterized by decreasing of its density, that was most visible in feather-grass steppe. In 2006-2012 the number of Little Bustard varied
from year to year, but dynamics from habitat to habitat had sometimes different trend. Since 2012, experienced rapid population growth, which was
probably due to the appearance of the gregarious locust forms. The situation
with the Great Bustard is absolutely different. The number of this specie in the
past 40 years is maintained at an extremely low level, without visible changes.
Key words: Great Bustard, Kostanai Region, Little Bustard, populations, number.