Pacific Island Network anchialine pool monitoring protocol: Narrative, version 1.0

Raikow, David; Brasher, Anne; Farahi, Anne; Kramer, K.; Kozar, Kelly; McKenna, Sheila; Hayes, Malia; Weijerman, Mariska; Monello, Ryan

The National Park Service created the Inventory and Monitoring Division to obtain information on the long-term trends in the condition of National Park System natural resources. This protocol defines methods to monitor animal populations of anchialine pools in Kaloko-Honokōhau National Historical Park (KAHO) and Puʻuhonua O Hōnaunau National Historical Park (PUHO). The protocol consists of a narrative (this document), quality assurance plan (QAP), and set of standard operating procedures. Anchialine pools are brackish coastal waterbodies receiving no regular overland flow, with groundwater inputs from both freshwater and marine sources that fluctuate with tides. Occurring on arid coastlines where freshwater is scarce, anchialine pools are a significant natural and cultural resource. Development, nutrient influx, groundwater withdrawal, and the introduction of non-native species threaten anchialine pool ecosystem health. Data obtained under this protocol will be used to help inform park management decisions in the face of such threats. The primary objective of this protocol is to quantify the annual abundance of select crustacean, mollusc, odonate, and fish species in order to determine if the population size of these species declines or increases over time within each pool. Pool selection was determined primarily by park management priorities, with the overall number of sites limited by logistical constraints of PACN. Native and non-native crustacean, mollusc, odonate, and fish species will be monitored in five pools at KAHO and three pools at PUHO. Additionally, only odonates will also be monitored at seven pools in KAHO, the only locations where the endangered orangeblack damselfly (Megalagrion xanthomelas) is consistently observed. A secondary objective of this protocol is to annually measure abiotic and biotic characteristics of the eight pools where crustacean, mollusc, odonate, and fish species are monitored. The abiotic and biotic characteristics selected for monitoring include: riparian vegetation species and % cover; a pool map and photographic record; geomorphology characteristics represented by canopy closure, substrate particle sizes, water depth, and detritus depth; light exposure measurements; and a suite of water quality measurements. Anchialine pools included in this protocol were identified as important resources by the parks and some of them are being actively restored. Thus, while they will not be analyzed statistically, abiotic and biotic data of pool characteristics will aid managers in understanding the effectiveness of management techniques and changes in the abundance of anchialine pool animals, should this occur. Animal abundance data will be reported to parks in an annual briefing that contains data for each species in each pool, a summary of data collection efforts to date, notable changes in pool habitat, and potential management concerns. A trend report and scientific review and revision of the full protocol will be produced after 10 years of data collection.

Pacific Island Network anchialine pool monitoring protocol: Narrative, version 1.0

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