THE ECOLOGY AND CONSERVATION OF THE ENDANGERED ENDEMIC SHRUB, KOWHAI NGUTUKAKA CLIANTHUS-PUNICEUS IN NEW-ZEALAND

Common in cultivation in New Zealand and elsewhere, natural population s of kowhai ngutukaka Clianthus puniceus (Fabaceae), an endangered New Zealand shrub, are rare in the wild (29 populations). Populations are generally composed of only a few plants occurring on north-facing (su nny) bluffs, cliffs, and lake and river margins, or on hillslopes in s eral scrub communities. At these remaining sites, plants were found to be mostly multi-stemmed, with a low, spreading growth habit. Turnover of stems was high, each plant losing and gaining approximately two st ems per year. Asexual reproduction occurred within populations by laye ring of branches up to 4 m from the parent plant. This characteristic improves persistence on sites, but genetic variability within populati ons is probably low. Populations produce abundant seed, suggesting ade quate pollination, but passive dispersal appears to limit spread. Howe ver, seed can survive for decades dormant within soil seed banks befor e germination. High foliar element concentrations suggest high herbivo re preference. Continuing threats to C. puniceus populations are loss of habitat, browsing by introduced mammals and molluscs, competition w ith adventive weed species for establishment on open sites, and overto pping within seral communities. (C) 1997 Elsevier Science Ltd.