Lorini and Persson (1994a,b) estimated a total population not exceeding 260 animals, divided into three subpopulations: that on the island of Superagüi (about 120 individuals), and two on the adjacent mainland, in the valleys of the Rios Patos and Branco (estimated at 35 individuals), and the valleys of the Rios Varadouro and Araçauba (estimated 100 individuals). As noted already, the northern limits to the range of L. caissara identified by Lorini and Persson (1990) were extended north into the state of São Paulo to the Serra do Cordeiro through the surveys of Martuscelli and Rodrigues (1992), but many localities were based on reports, which have yet to be confirmed (Valladares-Padua et al. 2000). The northernmost confirmed localities to date are those in the region Ariri, municipality of Cananeia (Rodrigues 1998), and Valladares-Padua et al. (2000) indicated that under any circumstances the populations there are extremely scarce. Both Martuscelli and Rodrigues (1992) and Valladares-Padua et al. (2000) found difficulties in surveying the region using interviews as a guide (people knew little or confused the species, felt intimidated, and in some cases were hostile).

A more recent population estimate for the Island of Superagui, based on transect work between 2000 and 2002, is 183 animals (Amaral et al. 2003); there are no recent population estimates for the mainland. The total current population is therefore for unlikely to exceed 400 animals at present.

Population densities are in the order of 1.5 individuals/km² or 0.30 groups/km² (Lorini and Persson 1994a). Amaral et al. (2003) reported an individual density of 1.66 individuals/km² or 0.38 groups/km² on Superagui.

Decreasing