What habitats do breeding hinds prefer when calving?

What habitats do breeding hinds prefer when calving?

Hinds travel a significant amount 1-2 days before giving birth, move very little for up to a week thereafter, then over several weeks gradually return to normal ranging behaviour (Fig 7). 

 hind movements around calving @ Invermay

Figure 7: Typical hind movement patterns around calving for a hind intensively farmed at AgResearch Invermay. Crimson line – normal activity prior to onset of calving; Red line – marked elevation in movement just prior to calving (on some farms this is seen as fence-line pacing); Green line – birth date; Blue line – post calving period.

In hill and high country environments the increased movement just prior to calving is often far less marked, but instead the hinds show a greater degree of reduced movement for 2-3 weeks after calving compared to more intensively stocked farms.

Hinds look for some form of cover to calve in and subsequently use it for at least for 1-2 weeks after calving.  Larger, most likely more dominant, hinds generally remain on sites dominated by improved pasture, while smaller, more submissive, hinds opt for higher elevation sites dominated more by tussocks.

Table: Hind 24hr post-calving vegetation selection (usage/availability) at Whiterock Station in 2008/09.

Vegetation type

 

 

GPS collared Hind

 

 

 

459

374

567

606

595

600

2365

Pasture

0.1

1.3

0.3

0.4

0.2

0.4

0.9

Tussock

0.1

0.1

3.5

2.6

4.4

3.6

0.3

Scrub

6.0

2.4

0.0

0.2

0.1

0.2

2.8

Values >1 indicate the hinds were selectively using the vegetation, while values <1 indicate the hinds were avoiding the vegetation. Several observed behavioural patterns indicated Hind 374 was a larger dominant hind in the breeding herd.

Hinds remain within 50-100 metres of the birthing sites for 3-4 days after calving. In the absence of predation, and perhaps reflective of the hinds’ contentment with the birthing environment, hinds prefer to stay with their calves.

Hinds in more intensively stocked paddocks (Fig 8) are more active – and probably more stressed - immediately prior to calving than in the hill/high country. This may reflect increased stress levels in those hinds, which is thought to be a major contributing factor to low calf survival. A high amount of pacing in a small paddock also significantly increases the chances that hinds with newborn calves will be disturbed, interrupting successful calf-dam bonding. 

Hinds showing increased movements pre-calving at different stocking densities 

Figure 8: Percentage (%) of GPS collared hinds showing increased movement 1-2 days prior to calving at the study sites, and an intensively farmed site (AgResearch Invermay) with hinds set-stocked at different densities.