Simultaneous multiple‐calf allonursing by a wild Masai giraffe

Abstract

1 INTRODUCTION Allonursing is when mothers nurse young that are not their own. It is rarely seen in wild giraffes (Giraffa camelopardalis). Pratt and Anderson (1979) reported that of 860 observations of nursing attempts, 37 were by an unrelated calf, and just one succeeded in sustained nursing. Saito and Idani (2018) documented only five of 76 allonursing attempts resulted in sustained nursing. Typically, the mother appeared unaware that the nursing calf was not her own, and thus, these studies concluded that the instigators of allonursing were unrelated calves stealing milk from unwitting mothers. Here, we report an instance of simultaneous allonursing by three giraffe calves in Tarangire National Park, Tanzania. This case is unusual in that the lactating female appeared to be aware of all three nursing calves and allowed nursing for an extended period of time (>1 min). 2 METHODS Since 2011, we systematically collected data on giraffes during 6 road‐transect surveys per year in a 1,500‐km2 area of the Tarangire Ecosystem, northern Tanzania, between latitude 3.27–4.08°S and longitude 35.73–36.23°E. The main vegetation communities are Acacia tortilis parkland, Acacia‐Commiphora woodland, gall Acacia drepanolobium woodland, Combretum‐Dalbergia woodland and open grassland (Lamprey, 1963). We identified individual giraffes from photographs using their unique and unchanging coat patterns (Foster, 1966) with the aid of pattern recognition software (Bolger, Morrison, Vance, Lee, & Farid, 2012). We did not genetically assign calves to mothers, but we assumed mother–calf pairs from extended suckling behaviour (>5 s) without rejection. 3 RESULTS AND DISCUSSION We documented 82 extended nursing bouts during 45 surveys from 2011 to 2019. All previous bouts were a single female and single calf. On 27 January 2019, we witnessed a remarkable case of simultaneous multiple‐calf allonursing. An adult female moved towards a group of calves (<1 year of age), and three of the calves immediately ran over and began suckling from her. We were not certain whether any of the calves were her offspring nor whether the calves were related to each other or to the female. The calves were slightly different sizes, and thus, we presumed different ages, and two were females, and one was a male (Figure 1). The adult female allowed this nursing for over a minute and did not actively reject the nursing calves. She appeared to be aware of the situation as all three calves approached her from the front and were in her view during nursing (Figure 1).