Floodwaters have isolated this area, with hardly any room left for patrolling by guards and watchers.
Around 1500 rare species of the swamp deer live in the forests in the reserve.
The Dudhwa has over 100 tigers and four leopards as per the official census undertaken last year. All of these endangered animals are also at risk.
Nearly three dozen wild species including swamp deer, hog deer and spotted deer were rescued by park officials in Dudhwa core area.