Statistical tests suitable for small data samples are used to compare the observed energies and angles of the SN 1987A neutrino events with distributions expected for a range of assumed temperatures and relative luminosities of different neutrino species. The highest confidence levels are obtained for simulated samples with an admixture of ${\nu }_{\mu }$, ${\overline{\nu }}_{\mu }$ and ${\nu }_{\tau }$, ${\overline{\nu }}_{\tau }$ added to the ${\overline{\nu }}_e$ interactions. This is a consequence of relatively high-energy thresholds [particularly for the Irvine-Michigan-Brookhaven (IMB) detector] and ${\nu }_{\mu }$, ${\overline{\nu }}_{\mu }$, ${\nu }_{\tau }$, ${\overline{\nu }}_{\tau }$ energies being greater than those of ${\overline{\nu }}_e$. It is also found that a ${\nu }_{\mu }$, ${\overline{\nu }}_{\mu }$, ${\nu }_{\tau }$, ${\overline{\nu }}_{\tau }$ admixture is more probable than a ${\nu }_e$ contribution for which the IMB detector is especially inefficient. A possibility of identifying ${\nu }_{\mu }$, ${\overline{\nu }}_{\mu }$ and ${\nu }_{\tau }$, ${\overline{\nu }}_{\tau }$ interactions from a future supernova collapse is also discussed.

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