Friends of Hakalau Forest National Wildlife Refuge
Summer 2022 Newsletter
Presidents' Perch Summer 2022

J.B. Friday

President, Friends of Hakalau Forest National Wildlife Refuge

In This Issue


Volunteer with us!

Congratulations Baron!

Research News

Bird Survey Summary

Hakalau Forest Says "Mahalo!"
There has finally been some good news for Hawaiian birds recently: the US Department of the Interior (which includes both the Fish and Wildlife Service and the Park Service) will be investing $14 million in programs to save the rarest of Hawaiian birds from extinction. The largest, most imminent threat to our forest birds are the mosquito-borne diseases: avian malaria and avian pox. Most of this new funding will focus on mosquito control and will support both research to develop and deploy methods of mosquito control and implementation on the ground control in Haleakalā National Park. While none of the funding will go directly to Hakalau Forest National Wildlife Refuge, the methods developed and the legal and procedural constraints overcome will eventually allow the Refuge to use the same technologies to control mosquitoes.

The leading technology currently, which has been used successfully elsewhere, uses incompatible male mosquitoes to breed with local females but not produce offspring. The males are incompatible because they will be inoculated with a different strain of the gut bacterium Wolbachia than local mosquitoes. This makes them sterile when they mate with local females. The Wolbachia technology does not involve genetic modification, so it should be the first technology to clear regulatory hurdles. Here is where you can help: there are already well-meaning but misinformed activists protesting what they think will be introduction of genetically modified mosquitoes into Hawai‘i. The Wolbachia technology does not involve genetic modification. Any chance you get to set the record straight and stick up for our birds, either in person conversation or on social media, will be appreciated.

To learn more about these technologies, listen to Stephanie Mladinich’s presentation (link below), go to, or read our Winter 2020 newsletter for an article by Chris Farmer of the American Bird Conservancy.
Volunteer with us!
Volunteer trips to the refuge resume.
After a long hiatus due to COVID, the Refuge is beginning to host volunteer trips again. The Friends have scheduled volunteer trips for Saturday July 9th and Thursday August 25th. Both will just be day trips, not overnights. Space is limited and preference will be given to Friends of Hakalau members (hint: if you want to go and you’re not a member, sign up:

We will also need volunteers who have 4WD vehicles who can help drive. Email us at to register.
Congratulations Baron!
Celebrating Baron Horiuchi's Retirement
Friends, under Jamie Tanino’s guidance, produced a coffee table worthy scrap book remembrance, with each set of pages produced by a different volunteer group that worked with Baron over the decades.

Mahalo for the memories Baron!
Gail Okata presented Baron with a remembrance quilt consisting of hard earned t-shirts contributed by volunteers. Many of the volunteers, including many who could not attend a rainy Volcano bento gathering for the presentation, contributed to a significant gift card at a favorite local garden shop presented by Nora Furono.

Pockets and pathways to invasion:
Monitoring avian disease-carrying mosquitoes in the face of climate change

Stephanie Mladinich
Tropical Conservation Biology and Environmental Science
University of Hawai`i at Hilo

Each spring the Tropical Conservation Biology and Environmental Science graduate program at University of Hawai`i at Hilo presents a symposium featuring five minute presentations by students on their research. This year the best presentation award went to Stephanie Mladinich for her research with Pat Hart at Hakalau entitled "Pockets and pathways to invasion: Monitoring avian disease-carrying mosquitoes in the face of climate change" which was partially funded by the Friends.

To listen to her presentation on the important early warning mosquito research being conducted on the refuge, please click the link below.
Bird Survey Summary

Steve Kendall
'Apapane in the refuge
Until I retired at the end of 2020, I was a Wildlife Biologist at the Big Island National Wildlife Refuge Complex. Near the end of that year, I was on a conference call where we trying to figure out a means to analyze several decades of forest bird survey data collected on the Refuge Complex. Someone jokingly said, “maybe that is something that Steve would like to do in retirement?”. I laughed it off, but then thought, “well there is the need, there is upcoming training on how to do the analyses, and it will only take a couple months to do, so sure”. One year later, we completed the first steps, analyzing the data and getting the results published in a U.H. Hilo Technical Report. We are now working on a manuscript that we hope to be published in a professional journal within a year.
For the Technical Report I worked with co-authors Rachel Rounds from the U.S. Fish and Wildlife Service, Inventory and Monitoring Program; Rick Camp from the U.S. Geological Survey, Pacific Island Ecosystems Research Center and Ayesha Genz from the University of Hawai‘i at Hilo, Hawai‘i Cooperative Studies Unit. For the manuscript, Refuge Complex Project Leader, Tom Cady and Deputy Project Leader, Donna Ball have joined the above team as co-authors.

The Refuge Complex was created for the conservation of endangered Hawaiian forest birds and their habitats. The Refuge complex consists of the Hakalau Forest Unit (HFU) on windward side of the island and the Kona Forest Unit (KFU) on the leeward side of the island. Forest bird surveys have been conducted at both units to monitor forest bird populations and their response to management. We analyzed survey data from 1987 to 2019 at the HFU and from 1995 to 2019 at the KFU. Survey data from HFU was last analyzed in 2016 with data collected through 2012. At KFU, data from surveys were analyzed in 2009 with data collected through 2005. We felt it was critically important to get a current assessment as environmental change and declines in Hawaiian forest bird populations have accelerated in recent decades.
Surveys at HFU have been conducted annually, but at more irregular intervals at the KFU. They were conducted in the spring to coincide peak breeding season and activity of forest birds. Methods are similar to those used during the Hawai‘i Forest Bird Surveys which took place in remaining forest habitats on the main Hawaiian Islands in the 1970s and 80s. We used a commonly utilized method called Variable Circle Point (VCP) counts or distance sampling. The counts were done on points laid out along transects. At HFU we used data collected from 226 stations and KFU data from 146 stations.

Trained and experienced ‘primary’ counters, following detailed protocols, conducted the surveys. Surveys occurred from dawn to 11:00 a.m. and were limited to periods of favorable weather conditions. With VCP counts, observers record all birds heard and seen and the distance the bird was from the observer. Bird survey participants also collected habitat and environmental data. All bird species were recorded at survey stations but for our analysis we focused on eight native species, Hawai‘i ‘elepaio, ‘ōma‘o , ‘akiapōlā‘au, Hawai‘i ‘amakihi, ‘alawī (formerly known as Hawai‘i creeper), Hawai‘i ‘ākepa, ‘i‘iwi, and ‘apapane and two non-native species, red-billed leiothrix and warbling white-eye (formerly known as Japanese white-eye). ‘Akiapōlā‘au, ‘alawī and Hawai‘i ‘ākepa are listed as endangered and ‘i‘iwi as threatened under the Endangered Species Act. ‘Ōma‘o were extirpated from the leeward side of Hawai‘i Island several decades ago and thus not detected at KFU. Also we had too few detections of ‘akiapōlā‘au, ‘alawī and Hawai‘i ‘ākepa at KFU to include them in our analysis for that unit.
We analyzed data by stratum. At HFU we based the strata on habitat; open-forest, closed-forest and afforested-pasture. The open-forest ranged from 1,400 to 1,920 meters elevation and was dominated by ‘ōhi‘a and koa/‘ōhi‘a forests. This stratum had been used for grazing historically, with a relatively intact tree canopy and naturally recovering understory following feral ungulate removal. The closed-forest ranged from 1,400 to 1,750 meters elevation and also was dominated by ‘ōhi‘a and koa/‘ōhi‘a forests. It was the least disturbed of the Refuge Complex habitats, as this area was not used for grazing. The afforested-pasture ranged from 1,650 to 2,000 meters elevation. Most of the trees in this strata at HFU had been removed historically by logging and grazing but have since been afforested with over 500,000 koa and native understory species. At KFU, we divided the study area by elevation at 1,524 meters. This is the elevation above which mosquitos and disease were thought to have little impact on forest birds. The upper strata ranged went up to 1,829 meters elevation and was dry, subalpine ‘ōhi‘a forests and mesic koa/‘ōhi‘a and ‘ōhi‘a forests. The lower stratum extended down to 1,067 meters elevation and was categorized as wet and mesic ‘ōhi‘a forest. Both strata at KFU were fenced but little ungulate control has taken place. Forest bird data has not been collected in the newly acquired lands at KFU.

We used the program Distance to calculate forest bird densities and populations. As mentioned above, observers recorded the distances from their location to the birds. The Distance program assumes that birds at closer distances are more likely to be detected with decreasing detection probability as distance from the observer increases. With Distance analysis a detection probability was estimated, which was then was used to compute density of birds. Density was multiplied by the area of the stratum to calculate population estimates. We used several covariates in the models including cloud cover, rain intensity, wind strength, observer, time of detection, type of detection (heard only, seen, or heard first then seen) and year. We then calculated populations for each year.

Table 1 shows population estimates for the final year included in our analysis. The most abundant species at HFU were ‘i‘iwi, ‘apapane and Hawai‘i ‘amakihi. At KFU ‘apapane were by far the most abundant species with densities far higher than previously recorded at that unit or elsewhere in Hawai‘i. Hawai‘i ‘amakihi was the second most abundant species at KFU. Population estimates of ‘i‘iwi were much lower at KFU compared to HFU.
After estimating population abundances, we then determined trends. The following tables show population trends for the entire study period at HFU (Table 2), the most recent decade at HFU (Table 3) and for the entire study period at KFU (Table 4). Trend was interpreted as upward = ↑, stable = ↔, downward = ↓, or inconclusive = Inc. NA = insufficient data. Trends with strong (0.7 < P < 0.9) and very strong (P > 0.9) probability are shown with double symbols.

We found that most of the species at HFU, had stable, long-term (1987–2019) population trends in the open-forest stratum, with only Hawai‘i ‘ākepa having a downward trend (Table 2). ‘Apapane and warbling white-eye had upward trends in this stratum. In the closed-forest stratum, all but three species had downward population trends. In the afforested-pasture, all species had upward trends. Results were mixed for the combined stratum estimates. Three of the native species, Hawai‘i ‘elepaio, ‘ōma‘o, and ‘i‘iwi, had stable populations. Two of the endangered species, ‘alawī and Hawai‘i ‘ākepa, had downward population trends, and results were inconclusive for the third endangered species, ‘akiapōlā‘au.
Population trends were somewhat different for the most recent decade at HFU (Table 3). Four species, ‘alawī, Hawai‘i ‘ākepa, ‘apapane and warbling white-eye had downward population trends in the open-forest stratum, but five species had stable populations, and the results were inconclusive for ‘akiapōlā‘au. In the recent decade, nearly all species had downward trends in the closed-forest stratum with only the ‘ōma‘o having an upward trend. Three of the more common species at the Refuge Complex, Hawai‘i ‘amakihi, ‘apapane, and warbling white-eye, had downward population trends in the afforested-pasture stratum in the recent decade. Results for ‘i‘iwi were inconclusive, but five species still had upward population trends in this stratum. Results were mixed for the combined stratum estimates. ‘Ōma‘o and ‘akiapōlā‘au had upward trends, but ‘alawī, Hawai‘i ‘ākepa, ‘apapane, and warbling white-eye had downward trends. Results were inconclusive for Hawai‘i ‘elepaio, Hawai‘i ‘amakihi, ‘i‘iwi, and red-billed leiothrix.
At KFU, Hawai‘i ‘elepaio had downward population trends in the upper stratum and upward trends in the lower stratum (Table 4). Trends were inconclusive for Hawai‘i ‘elepaio when we combed the two strata, but tending towards upward. Hawai‘i ‘amakihi were stable in both strata and overall. ‘I‘iwi trends were downward in the upper stratum, inconclusive in the lower stratum, and downward overall. ‘Apapane trends were upward in both strata and overall.
In summary, we found that management actions implemented thus far have benefited forest birds at the Refuge Complex, but it appears that additional stressors, such as habitat alteration, disease, feral ungulates or predators, may be having negative influences. About half of the species continue to have upward or stable long-term trends at both Refuge Complex units. Management actions have been particularly beneficial in the afforested-pasture and open-forest strata at HFU, although trends have become more downward in the recent decade for some species. ‘Alawī, Hawai‘i ‘ākepa and ‘apapane, have especially strong evidence of downward population trends in those strata. The afforested-pasture supports a relatively small proportion of HFU populations, but likely will become more important as it regenerates/matures and as the mosquito-line moves up. At KFU, population trends were mixed with more species having downward trends in the upper stratum and upward trends in the lower stratum, which was unexpected as the lower stratum is below the mosquito line and more heavily affected by invasive species. There were few endangered birds at KFU and populations of ‘i‘iwi were declining.
The Refuge Complex remains one of the more important conservation areas for forest birds in the State of Hawai‘i. We compared the 2019 Refuge Complex populations estimates to estimates of State-wide populations and found the Refuge Complex supports large proportions of the global populations of four listed forest bird species: ‘akiapōlā‘au (61%), ‘alawī (71%), Hawai‘i ‘ākepa (44%), and ‘i‘iwi (20%).

Several topics are being considered in the manuscript that we are working on and include:
  • What changes have occurred in trends since the previous analyses?
  • How do trends at the Refuge Complex compare to other sites in Hawaiʹi?
  • Could climate change driven shifts in phenology impact surveys, which have been done at the same time of year for decades?
  • Identifying threats to forest bird population and management actions that could be implemented to mitigate these threats.
  • Habitat loss
  • Avian disease
  • Feral Ungulates
  • Predators
  • How can we collaborate with adjacent landowners to advance forest bird conservation?

Hakalau Forest Says "Mahalo!"

Marcia Stone

It was a blue-sky kind of day. The sun was high, the air was cool, and the path broad and
easy. A dozen plus members of O'ahu-based Hawaiian Trail & Mountain Club (HTMC) were
atop Mauna Kea in Hakalau Forest. Binoculars in hand, they took in a small section of the
33,000 acres of revitalized native forest habitat and the last refuge for many of our native birds.
Last year, HTMC made a donation from their Preservation Fund to our Endowment Fund. The
Friends of Hakalau Forest were delighted with HTMC’s interest and help. And because
Hakalau is difficult to access and to say thank-you for the donation, the Friends of Hakalau
facilitated a special trip for 15 members of HTMC. Hakalau itself is its most eloquent
spokesperson, and it is important to allow people from all our islands to hear its voice. So,
Mike Scott, the chair of the Endowment Committee, had the inspiration to donate his one-time
use of a van from Hawaii Forest & Trail; and I, as a member of HTMC, contacted their board to
find a dozen members who would like to experience a rare opportunity. These folks were
joined by a few more members from the Big Island.
Hawaiian Trail and Mountain Club in front of a blooming lobelia.
photo John Hoover
On March 25th, a van from Hawaii Forest & Trail, with owner Rod Pacheco as a guide, brought most of the members up 6,500 feet to the gated reserve on the eastern slope of Mauna Kea. A few minutes ahead of them, another van ferried four more members with Jack Jeffrey, the renowned bird photographer, as guide. With two professional naturalists by our side, we had five hours to enjoy this all-native environment, spot rare birds and plants and have a provided picnic lunch with much
camaraderie. What we saw is a koa-'ōhi'a forest with a lush understory, including ‘akala and lobelia in bloom. We had to watch where we stepped there was so much native mint underfoot. And overhead we were greeted with all the songs of the 'i’iwi, 'apapane, ‘ākepa and others. There was never a moment a bird wasn’t singing.
The time flew, but the ‘akiapōlā’au had evaded our spotting, although we heard it. Just as we were about to turn around, Jack Jeffrey spotted a bright yellow male. Luckily our group was all together, so we all got a good look at this insect eater with the unusual bill which can drill into koa branches and scoop out its food. When the ‘akiapōlā’au flew off, one person pointed into the blue overhead and said, “Is that a hawk?” We all looked skyward. High, high above us was a large adult ‘io soaring and then hovering, just long enough to let everyone’s camera go click, click, click. Hakalau Forest certainly opened its bounty to us that day!
The Friends of Hakalau is a membership organization. Membership dues and donations to the Friends are our only source of funds allowing us to cover our expenses (for example this newsletter) and to make grants.
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Every Wednesday on HPR listen to Manu Minute created by Patrick Hart, member of the Friends since its inception and a board member for multiple terms. Click the button to hear the segments that have already been aired.
Friends of Hakalau Forest, National Wildlife Refuge is a 501 (C)(3) organization and is recognized as a tax exempt non-profit organization by the Federal government and the State of Hawaii. We appreciate and thank you for your membership and your donations.

   J.B. Friday
Vice President
   Debbie Anderson
   Bret Mossman
   Blaire Langston

Members at large
Charlene Akina
Ken Kupchak
Mike Scott  
Rob Shallenberger
Peter Stine
Marcia Stone 
Jaime Tanino
Gaylord Wilcox