Ecosystem ManagementEMP Program Bulletin Volume 51 Autumn 2010 Pōhakuloa Training Area’s Inside this issue: Natural Resources Office takes Pōhakuloa Training Area's Natural Resources Office takes action to preserve the Mauna Kea action to preserve the Mauna pāmakani during extreme drought, Kea pāmakani during extreme By Tiana Lackey...................................................1 Tiny alien snails put natural resource workers drought in a salty situation, By Candace Russo.....................3 By Tiana Lackey Alien snails found in plant nurseries - can we HE MAUNA KEA pāmakani keep them out of our native forests? . T(Tetramolopium arenarium By Matt Keir & Candace Russo.............................6 ssp. arenarium) is a member of Volunteers lend a hand to help Nīoi habitat, pāmakani the sunflower family that was By Kim Welch.....................................................7 listed as endangered in 1994. In the wild, these Extent of threats posed by non-native garlic snail species are now only found at Pōhakuloa Training Mauna Kea Mauna Kea PTA-NRO) Jen Lawson, by (Photo (Oxychilus alliarius) still unknown, Area (PTA) on the island of Hawai‘i (U.S. Fish & Wild- By Stephanie Joe & Candace Russo......................8 life Service [USFWS], 2003). The primary threats to this species include: feral ungulates, who eat the Staff Spotlight: Vince Costello - OANRP's Rare plants; competition from invasive plants; and fire. Snail Conservation Specialist................................10 Over the past year, drought has emerged as an ad- mined that the viability of the only known popula- ditional threat to this and other listed species at PTA. tion of Mauna Keapāmakani would be unsustain- The National Weather Service recently an- able without taking action. nounced that the 2009-2010 Hawaiian Islands wet As a result of the current drought and the rapid season was the driest in the past 30 years, and the increase in mortality of the Mauna Kea pāmakani, National Drought Mitigation Center has ranked the PTA NRO decided to initiate an emergency man- Hawai‘i as the driest state in the nation (National agement response. Managers re-prioritized program Weather Service, 2010). On July 19, 2010, the U.S. resources in order to initiate a supplemental water- Department of Agriculture (USDA) designated all ing effort. The goal of the watering effort was to sus- four Hawai‘i counties as primary natural disaster tain the remaining plants until the onset of normal areas due to losses caused by the continuing drought (USDA Farm Service, 2010). Most of PTA is cur- rently experiencing extreme (D3) or exceptional (D4) drought. Rainfall between January and July 2010 in Mauna Kea pāmakani habitat totaled 1.19 centimeters (0.47 inches), about 3% of the normal annual average. The dry winter has had a serious impact on Mauna Kea pāmakani population numbers. The number of individuals dropped from 693 in 2006 to just 27 in Water-stressed Mauna Kea pāmakani (left), on the first June 2010, with the greatest decline (80%) between day of watering. The same plant (right), three months 2009 and 2010. later, showing improved plant vigor. (Photos by Tiana PTA Natural Resources Office (NRO) staff deter- Lackey, left; and Lisa Castle, right, PTA-NRO) rainfall levels. on 62% of the plants. Weather data were analyzed to determine the 2) What potential effects will continued tram- amount of water that would be needed to simulate a pling and soil compaction (due to the watering pro- meaningful rainfall event. NRO staff determined that cedures) have on the plants? approximately ½-gallon of water per plant would 3) Significant resources have been allocated to be adequate, so drip-irrigation bottles were used to save the few remaining plants, but at what point deliver this amount to each plant over four hours. does this sacrifice become detrimental to other Army biolo- conservation measures at PTA? Disproportionate al- gists tracked the location of limited personnel and financial resources following infor- toward one species may have negative consequenc- mation for each es for others, especially during extreme climate plant: location; conditions. plant identifica- 4) How will the NRO staff proceed if ultimately tion number; vig- the survival of this species becomes dependant on or; evidence of continued intensive management? browse; number These guiding ecological and philosophical ques- of reproductive tions will continue to be discussed by managers. The structures; pres- immediate question of how long to water the plants ence/absence of is the least difficult to answer. Resource managers ants and scale; have installed a rain gauge at the site to help deter- Drip irrigation bottle used to provide and percent mine when natural rainfall is adequate to reduce or supplemental water to the Mauna cover of weeds. cease supplemental watering. Until enough rainfall Kea pāmakani. (Photo by Mona Biologists also data are acquired to make a responsible determina- Tatum, PTA-NRO) took pictures tion, the dedicated staff at the PTA NRO will continue of each plant on a rotational basis to record visible to devote time and resources to preserving the changes in plant vigor. endangered Mauna Kea pāmakani. • Plants were initially watered once a week, and REFERENCES after eight weeks, the frequency of the watering was National Weather Service. 2010. Drought Information State- reduced to once every two weeks. ment. HIC001-003-007-009-062200. Honolulu, Hawai‘i. In June, 2010, there were 27 naturally occur- August 5, 2010. ring Mauna Kea pāmakani at PTA, however only 4% United States Department of Agriculture, Farm Service. 2010. of these plants were healthy, with 96% in poor or USDA designated all four Hawai‘i counties as primary natural disaster areas. Media Release 031. Honolulu, moderate health. As of October 6, this population Hawai‘i. July 21, 2010. of Mauna Kea pāmakani consisted of 8 adults and 4 U.S. Fish and Wildlife Service. 2003. Biological Opinion of the juveniles. Even though 15 of the 27 plants (or 56%) U.S. Fish and Wildlife Service for Routine Military Training have died since watering began in June, the health and Transformation of the 2nd Brigade 25th Infantry Divi- of the remaining plants has dramatically improved. sion (Light), U.S. Army Installations, Islands of Hawai‘i. Of the 12 individuals that were alive in October, 92% ACKNOWLEDGEMENTS: were healthy and 8% were in moderate health. Jen Lawson, Lisa Castle, Springer Kaye, Mona Tatum, Steve Additionally, 58% of the remaining plants had Evans, Kathy Kawakami, Nikhil Inman-Narahari, Lena Schnell, reproductive structures, a hopeful sign for reproduc- Peter Peshut, the PTA Weed Crew and Fuel Break Crew, and the rest of the dedicated staff at the PTA Natural Resources tion and a potential contribution to the seed bank. Office for their technical assistance, field support, persever- As supplemental watering for the Mauna Kea ance, and dedication which made this project happen. pāmakani continues, difficult questions have arisen for NRO managers to consider, including: ~Tiana Lackey is a botanical 1) Will supplemental plant watering produce un- coordinator with CSU-CEMML, foreseen or unintended consequences? For example, working for the PTA after four days of supplemental watering, invasive Natural Resources Office. ants and scale (previously unobserved) were found EMP Bulletin, Vol. 51, Autumn 2010 Page 2 Tiny alien snails put natural nurseries. Unfortunately, these plants were later found infested with alien snails prior to entering the resource managers in a salty OANRP facilities. To solve this part of the problem, the OANRP ceased accepting material from other situation nurseries. By Candace Russo The next step was to focus on eliminating the problem inside the nurseries. In the beginning, a N LATE 2008, the O‘ahu Army Natural Resources hot-water plant “shower” was employed, on loan IProgram (OANRP) discovered both their low- and from the Hawai‘i Department of Agriculture. Al- mid-elevation endangered plant nurseries harbored though this method worked on several of the snail several species of alien snails. Please see “Alien species tested (Zonitoides arboreus and Liardetia Snails Found in Plant Nurseries – Can We Keep Them doliolum, specifically), it did not work to eliminate Out of Our Native Forests?” insert following this ar- Succinea tenella. Moreover, seven of the 26 endan- ticle for more information and a list of species. gered plant species that were tested in the hot water The OANRP’s policy requires all plants be free of shower did not survive, which was “unacceptable,” pests prior to outplanting back into the wild, so the according to Lauren Weisenberger, propagule man- alien snails discovery presented a challenge. agement specialist for the OANRP. “We had to decide whether or not we should Instead, all nursery benches were power-washed, halt all planned outplanting activities even though bleached and placed in buckets of salt to prevent initially only some of the plants had snails,” said movement of new snails onto the benches. Each Matt Keir, rare plant program manager for the of the roughly 4,500 plants was then meticulously OANRP. “At that time, we did not have a way to examined visually (on the plant, on the pot, on the thoroughly check all the plants, so the decision was soil surface and in the soil when the plant was re- made to stop all planting and start inspections.” moved from the pot) for alien snails and their eggs, There were no records of any of the alien nursery snails yet in the forest outplanting