December 29, 2015
Aerial view of MCR showing thousands translocated native plants.
In the kind of world we’re living in it’s easy to get discouraged. But the word is out: Conservation works! In a new scientific publication in Plant Ecology with the prosaic title of “Monitoring results from a decade of native plant translocations at Makauwahi Cave Reserve, Kaua`i,” Lida and I distilled the actual life-history data collected at regular intervals for 10 years or more on 3,388 translocated native plants of 81 species, and were really pleased with what we found.
If they could talk, these plants would tell all of the staff members, volunteers, and several thousand local school children that they have not wasted their time in planting, maintaining, and monitoring the multitude of native and Polynesian plants now covering the abandoned cane fields and mine spoil at Makauwahi Cave Reserve. Averaged across all native species, three-quarters of all plants have survived long-term. Our “crazy notion” to use the adjacent fossil record of plants growing there a few centuries ago paid off handsomely, as these species had survival rates comparable to the native species that were growing on or near the site before we embarked on our quest. By using the fossil record to suggest plants to try, we doubled the list of plants on the site.
A whopping 80% of the native plant species have flowered on the site, and 70% have produced seed. Unaided recruitment, that is, volunteer seedlings coming up without us having to do anything, was a surprising 43%, and included some extremely rare plants. Among plants that died during the decade of study (2005-2015) primary mortality factors were transplant shock, irrigation failure, and human error (accidentally cutting, pulling, or trampling – some of us are experts at that). Insect damage, disease, and pigs were surprisingly, much lower. Although pigs for instance can wreak havoc, they don’t last long in our restorations because pigs have a high mortality rate in our area, thanks to our pig-hunter friends, and many of our acres are securely fenced now anyway.
One important finding for future efforts: translocated volunteer seedlings of native plants are the absolute champs at survival, often at or near 100% even for rare species. Another was that a restoration of this type can yield vast amounts of native plant seeds for other restoration projects. Taking only one-fifth or less of the seed available, in a one-year period our group harvested over 5 million seeds from 25 native dry forest species, many for use in the restoration of uninhabited Lehua Islet, near Ni`ihau.
Realizing this potential, State and Federal agencies and Grove Farm Company have helped us to develop our Native Plant Nursery, including a 20 X 60 foot greenhouse and the capacity to supply hardy native dry-adapted plants and seeds for other restorations on Kaua`i. If you have a project that needs native plants, contact us at email@example.com or call (808) 651-2479. We can supply hundreds or even thousands of some species, with advance notice.
Like a huge living organism, Makauwahi Cave Reserve has become something that to us is very heart-warming: a restoration project that spawns other restoration projects. Help us make 2016 a great year for conserving Hawai`i’s increasingly rare dry forests and coastal shrublands.