This small reserve is very rich in plant species with 178 species recorded including 118 species of flowering plants.
These include two rare or threatened species -
the Mueller daisy (BRACHYSCOME MUELLEROIDES) that is nationally vulnerable and endangered in Victoria and Reader's daisy (B. READERI) that is rare in Victoria. Ulupna is especially important for the Mueller daisy because the species is geographically restricted, occurring only here and in some other parts of Barmah Forest.
Ulupna is also an important faunal habitat, particularly for bird species with a high diversity of 101 species recorded. Of these, two are rare woodland birds -
the grey-crowned babbler (POMATOSTOMUS TEMPORALIS) that is endangered in Victoria and
the nationally vulnerable superb parrot (POLYTELIS SWAINSONII).
The grey-crowned babblers resident at Ulupna are part of an important remnant population of a species that was once common in the woodlands of south-eastern Australia but has suffered decline and fragmentation primarily as a result of habitat destruction and extensive modification of soil/ litter layers.
Ulupna also provides attractive habitat for superb parrots at the southern end of their range.
Unlike the remainder of the Barmah forests, Ulupna Reserve has suffered remarkably little from the impacts of grazing and logging. Therefore it is an important reference area for studies of the impacts of these activities on the red gum forests of the region.
Ulupna also contains an excellent example of river red gum (EUCALYPTUS CAMALDULENSIS) open forest.
The Commission has determined that this place has Indigenous values of national estate significance.
The Commission is currently consulting with relevant Indigenous communities about the amount of information to be placed on public record.
It is possible that non-indigenous cultural values of national estate significance may exist in this place.
As yet, the Commission has not identified, documented nor assessed these values.
The reserve is situated on the Murray Valley flood plain. The Island has a mass of waterways which dry up during periods of drought. Billabongs occur in the central section of the reserve. The vegetation of the reserve is mainly river red gum (EUCALYPTUS CAMALDULENSIS) open forest. The forest has a grassy understorey with species including pink bindweed (CONVOLVULUS ERUBESCENNS), austral cranesbill (GERANIUM SOLANDERI), sprawling bluebell (WAHLENBERGIA GRACILIS), cut-leaf goodenia (GOODENIA PINNATIFIDA) and wallaby grasses (DANTHONIA spp). Other tree species found in the reserve include yellow box (E. MELLIODORA),
grey box (E. MICROCARPA), cherry ballart (EXOCARPUS CURESSIFORMIS), weeping pittosporum (PITTOSPORUM PHYLLIRAEOIDES), lightwood (ACACIA IMPLEXA) and silver wattle (ACACIA DEALBATA). The forests and waterways of the area support a large number and diversity of bird species including ibis, ducks, kites, eagles and cormorants. Koalas have been re-introduced to the area with over 150 individuals now living here successfully.