Kia’i Moku Column — Maui Invasive Species Committee (MISC)

Coconut palms are woven into the culture of the islands; a beetle threatens that connection

Posted on November 16, 2023 by Lissa Strohecker

*Baskets woven from coconut leaves. Photo from Maui Nui Botanical Garden*

Would-be weavers spilled out of the shade under an open-sided tent at the Arbor Day event at Maui Nui Botanical Garden. Holding coconut leaves, they patiently worked the material back and forth in intricate patterns. At times, chatter came from the tent; other times, it was silent, brows furrowed in concentration. The kumu, master weaver Pōhaku Kaho’ohanohano, moved among the weavers, getting some started while trimming up and tying off the finished creations of others. Novice weavers hugged the kumu, beaming as they walked away with a new hat, bag, bowl, toy, or ornament created from a diminishing pile of leaves.

Coconut weaving is a tradition that dates back thousands of years throughout Polynesia. Coconut palms were first brought to Hawai‘i with the Polynesians. The coconut plant is akin to a pre-contact department store; it can meet needs and wants. Food (coconut meat) and drink (coconut water), material for building shelters, making rope, and weaving mats, bowls, and storage containers all come from the coconut. It’s even used for games and in ceremonial practice; the nut is used in ‘awa ceremony.

But the future of coconuts in Hawai‘i is at risk from a pest accidentally introduced to Hawai‘i. The coconut rhinoceros beetle is spreading on O‘ahu and has begun to reach other islands.

*The adult coconut rhinoceros beetle is nearly two inches in length, but because it’s nocturnal, it’s rarely seen. Photo courtesy Coconut Rhinoceros Beetle Response*.

At two inches long, the CRB is a beefy beetle, but it isn’t going to fly interisland on its own. Knowing what you are moving and where it comes from is the first step in preventing the coconut rhinoceros beetle from reaching Maui. By being alert to signs of CRB damage, a vigilant community can help find the pest early and keep it from becoming established.

*Bore holes made as the beetle eats through the crown indicate the beetle’s presence. Photo courtesy Coconut Rhinoceros Beetle Response*.

There are prevention measures in place. In October of 2023, the Hawai‘i Department of Agriculture (HDOA) instituted a temporary, one-year rule prohibiting the movement of high-risk material from O‘ahu to the rest of the state to reduce the risk of spreading coconut rhinoceros beetle. As of October, the following items cannot be moved without a permit: palm plants; decomposing plant material, such as compost, wood, or tree chips; mulch; potting soil; and other landscaping products that may harbor CRB.

These safeguards reduce but do not entirely eliminate the risk of spreading CRB. Here are steps you can take to keep the beetle at bay.

For Maui County, soil, compost, and mulch are the greatest risk. Contractors and landscapers bringing in container loads are doing so by permit, but careful sourcing – checking with the vendor if material came from infested areas – can prevent contamination. Homeowners purchasing bagged landscaping products are advised to be alert as well.

Why? It turns out that bags aren’t much of a barrier to a beetle that can chew through coconut trees. Even if the compost, mulch, or soil wasn’t sourced from an infested area, if bagged soil sits in an infested area, an adult beetle lay eggs in it. The first detection of CRB on Maui was a dead adult found in bagged soil; this was also the suspected vector of CRB found recently on Hawai‘i Island.

CRB larvae are found in soil, compost, and muclh. Larvae crawl on their side and if you suspect you have found one in Maui County, take a video and submit a report to 643PEST.org. Photo courtesy of Coconut Rhinoceros Beetle Response.

Know where your soil and compost are coming from and check for boring holes in bags and larvae. Storing material in closed containers will prevent beetles from laying eggs in them.

The quarantine rule also prohibits shipping coconut plants from O‘ahu that are taller than 4 feet to allow thorough inspection, but the soil in these and all potted plants could be a vector. CRB eggs are only about the size of 1/3 of a tic tac.

As CRB populations on O‘ahu continue to grow, the risk of accidentally transporting the beetle interisland will increase. Visit crbhawaii.org to learn more about distinguishing the Coconut Rhinoceros Beetle from similar-looking species and to see photos of palm damage that can indicate an infestation. Contractors and landscapers can find best management practices to reduce the risk of introducing CRB on the MISC website.

Find details about the interim rule on HDOA’s website. Report suspicious larvae and palm damage through the 643PEST.org reporting system. We need everyone’s kōkua to help protect Maui Countyʻs coconuts, from the royal grove in Kapuāiwa on Molokai to the palms that shade the beaches of Hāna.

Lissa Strohecker is the public relations and education specialist for the Maui Invasive Species Committee. She holds a biological sciences degree from Montana State University. Kia’i Moku, “Guarding the Island,” is prepared by the Maui Invasive Species Committee to provide information on protecting the island from invasive plants and animals that can threaten the island’s environment, economy and quality of life.

This article was originally published in the Maui News on November 10, 2023, as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

Read more Kiaʻi Moku articles

Protecting ‘Ōhi‘a: Fencing for the Trees

Posted on July 27, 2023 by MISC

Ungulate rubbings or browsing on Haleakalā sandalwood tree are seen in Polipoli. — FOREST AND KIM STARR photo

“The fungus needs an entry point,” says Marc Hughes, a research plant pathologist with the U.S. Forest Service in Hilo. He’s talking about the disease that is decimating ‘ōhi‘a lehua in parts of Hawai‘i. An untreated scrape on a person’s skin can lead to a staph infection; a similar but more drastic result is true for ‘ōhi‘a. When some external force breaks through a tree’s bark, invading pathogens can gain access to exposed tissues, and damage or kill the tree.

Ceratocystis lukuohia and Ceratocystis huliohia are fungal pathogens that cause the disease called rapid ‘ōhi‘a death, or ROD, so named because the trees appear to die within days or weeks. Both pathogens will kill ‘ōhi‘a trees, but lukuohia is more aggressive. Once infected, the tree responds, trying to slow the disease.

“It’s like a speed race,” explains Hughes, “but the fungus is faster.”

The crowns turn yellowish, then brown. The tree looks frozen, dead leaves still attached. By the time an ‘ōhi‘a tree shows symptoms, its days are numbered. Since it was first identified in 2014, rapid ‘ōhi‘a death has killed over a million trees, mostly on Hawai‘i Island, but trees on O‘ahu and Kaua‘i have also succumbed. A single infected tree was discovered and removed in East Maui in 2019 and, to date, is the only known occurrence in Maui Nui.

Wounding is a prerequisite. Plants with intact bark don’t become infected, even when directly exposed to the fungi. How does wounding happen? Wind is one way, says Hughes, who describes Tropical Storm Iselle as a “mass wounding event.” The 2014 storm battered portions of Hawai‘i island, breaking ‘ōhi‘a branches and toppling trees. Researchers observed a spike in ‘ōhi‘a mortality after the storm and linked the spread to increased windborne spores and tree damage. Ambrosia beetles, which may burrow into trees killed by rapid ‘ōhi‘a death, also play a role. Fungus-contaminated frass — the sawdust produced when beetles bore into wood — gets picked up by wind, animals and hikers’ boots, or falls into the soil. Studies indicate a strong tie between the presence of ungulates, such as pigs, cattle and goats, and rapid ‘ōhi‘a death. The large numbers of axis deer on Maui, Molokai and Lāna‘i likely mean ‘ōhi‘a trees in Maui Nui could be especially vulnerable if rapid ‘ōhi‘a death were to become established here.

The study on Hawai‘i island found that unfenced areas, where ungulates were present, had two to 69 times more evidence of rapid ‘ōhi‘a death-impacted ‘ōhi‘a than neighboring, fenced areas that were ungulate-free. Researchers are also looking into the relationship between ungulates and the presence of the fungi in soil samples. Initial results indicate a similar link: the presence of ungulates means a higher likelihood the destructive fungus will be detected. Flint Hughes, a research ecologist also with the U.S. Forest Service (and unrelated to Marc), thinks pigs may spread the fungus through ‘ōhi‘a roots when they dig up the ground searching for food.

While the potential scale of impacts to ‘ōhi‘a might seem overwhelming, there is hope. In 2022, students on Oahu helped convinced the Legislature to designate ‘ōhi‘a lehua as the Hawai‘i State Endemic Tree, honoring its importance to the ‘āina and Hawaiian culture. Protecting forests through fencing, ungulate removal and ongoing maintenance, is a straightforward strategy, and one that watershed partnerships across the state are already working to implement.

This strategy has public support. A recent survey conducted for the Coordinating Group on Alien Pest Species found that 89 percent of respondents know about ‘ōhi‘a and 80 percent had heard of rapid ‘ōhi‘a death. An impressive 93 percent supported fencing of high-value forests and removing ungulates to protect ‘ōhi‘a from rapid ‘ōhi‘a death. Support may also be coming from federal coffers. This March, the Hawai‘i congressional delegation announced efforts to secure $55 million over a 10-year period for rapid ‘ōhi‘a death-related research and management.

In closing comments during a 2022 presentation, Flint Hughes offered a reminder: “We tend to think of ‘ōhi‘a as forests. Every ‘ōhi‘a tree is an important individual. Some of these trees are 300 or 400 years old. We should respect that and them, and do what we can to protect them.”

To learn more about how to support efforts to protect ‘ōhi‘a, visit www.rapidohia death.org.

* Teya Penniman is the interim manager with the Maui Invasive Species Committee. She has 30 years’ experience in natural resource management and advanced degrees in law and management. “Kia’i Moku, Guarding the Island” is written by the Maui Invasive Species Committee to provide information on protecting the island from invasive plants and animals that threaten our islands’ environment, economy and quality of life.

UPDATE November 2023: Learn more about the correlation between tree damage and Rapid Ohia Death in the interactive storymap from the ROD Working Group

This article was originally published in the Maui News on April 8, 2023 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

Read more Kiaʻi Moku articles

Is ant-watching really a thing?

Posted on March 14, 2023 by MISC

By Monte Tudor-Long

If you list the different birds in your yard, you might come up with 15 to 20 species: myna, spotted dove, cardinal, perhaps a kolea or occasional nene flying over. It may come as a surprise, but you probably have just as many species of ants near your home.

You might ask, “Who cares? If you’ve seen one ant, you’ve seen ’em all!” But as with bird-watching, there’s a certain aesthetic to ant- watching. Just as birds are diverse and interesting to look at, the same can be true for ants. Check out Maui’s ants up close and you will discover a lot of variety. In addition to knowing more about the curious lives of these tiny cohabitants, what you learn could help stop the next invasion.

Ants are globally widespread and abundant, but all 50-plus species in the Hawaiian Islands were accidentally introduced by humans. Scientists and decision-makers concerned about invasive species look at impacts on residents, and also how invading species alter native ecosystems, and change agriculture, tourism, hunting and more. Different ant species may affect all, some or none of these realms. Our understanding of the problems caused by introduced ants comes from our knowledge of which ants are present, when they got here and where they can be found. Informed decisions require good information, and citizen scientists are a great source of important data on invasive species.

Observing and collecting ants can be easy and fun, and kids seem especially good at it. The first little fire ant ever collected in the United States was found by an 11-year-old girl in Florida; a 12-year-old boy in Alabama discovered the first red imported fire ant in the U.S. For both children and adults, ant-watching can be a gateway into new ways to observe, learn about and care for the ‘aina.

Ants you might find on Maui: graceful twig ant (center) as well as (clockwise from top left) the sickle-toothed ant, black house ant, yellow crazy ant, Emery’s sneaking ant, little yellow ant, African big-headed ant, tropical fire ant and ghost ant. — MELODY EUPARADORN / Hawaii Ant Lab image

One kind of ant can be as different from the next as a parrot is from a duck. You’ve probably encountered a species or two of pest ants inside your home, but most ants on Maui are not interested in your kitchen. Some indoor pests, such as black house ants, African big-headed ants, little yellow ants and ghost ants have a fondness for sweets. Ants in our yards include omnivorous ants, seed-eating ants, predatory-specialist ants, blind ants and others. The sickle-tooth ant specializes in eating pill bugs and sow bugs. The tropical fire ant, a serious outdoor pest, likes to eat grass seeds. Yellow crazy ants practically ignore people but are devastating to native ground-nesting seabirds. Graceful twig ants often nest in dead twigs in kiawe trees. Sneaking ants seem to prefer living in the most marginal, disturbed habitats available, like road medians and other sparsely-vegetated areas.

When you notice how different these ants appear, it might be less surprising that their social structures, where they live and what they eat are very different from each other.

Bird-watching is a popular hobby, and citizen-scientist bird-watchers enter tens of millions of sightings into online databases every year, giving conservation managers a wealth of data to help guide decision-making. The same cannot be said of ants — yet. Because they are tiny, it can be hard to tell one ant from another. But if you overcame that barrier, wouldn’t it be interesting to know all the different ants in your yard, and learn a little bit about their lives and natural histories? Since the year 2000, more than a dozen new introduced ant species have been recorded on Maui, including one last year. By becoming an ant sleuth, you just might be the one to find the next new species.

Spend some time in your yard, collect some ants and send them to the Maui Invasive Species Committee for identification. In return, you’ll receive information about the species of ants you found. You can start building a list of ants on your property. Collecting ants is simple: put a tiny bit of bait (peanut butter or mayo) on several 4-to-5-inch pieces of cardboard, leave them in shady spots around the yard for an hour and then freeze them in a ziptop sandwich bag. Mail your samples to MISC, P.O. Box 983, Makawao 96768. Questions? Contact miscants @hawaii.edu.

* Monte Tudor-Long is an early detection specialist with the Maui Invasive Species Committee, focusing on ant identification, natural history and ecology. He holds a bachelor’s degree in environmental studies from the University of California at Santa Cruz. “Kia’i Moku, Guarding the Island” is written by the Maui Invasive Species Committee to provide information on protecting the island from invasive plants and animals that threaten our islands’ environment, economy and quality of life.

This article was originally published in the Maui News on March 11, 2023 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

Read more Kiaʻi Moku articles

The race to protect Hawaii’s native forest birds from extinction

Posted on February 13, 2023 by Serena Fukushima

The upland realm of wao akua captivates all senses. Freshwater percolates into the earth, perfuming the cool air, and hues of greens and pops of red lehua delight the eyes, but the sound of its most charismatic denizens – the forest birds – is unique in all the world. These jewels of our rainforests – the honeycreepers – once had 54 different species. Today, only 17 remain, and some, like the kiwikiu, have fewer than 200 individual birds. Their plight is mainly due to a sound out of place in a Hawaiian forest – the buzz of a mosquito.

Hawaiian honeycreepers are an integral part of native ecosystems and Hawaiian culture. Some birds, like the ʻiʻiwi (left), developed long, curved bills to sip nectar out of crescent-shaped flowers, which both feed the bird and pollinate the plant. Kiwikiu (middle), developed sturdy beaks to snatch insects from tree bark. The ʻākohekohe (right) is Maui’s largest honeycreeper and has a feather duster tuft on its forehead to help aid in forest pollination. — James Petruzzi, John Crawley, Jim Denny photos (from left)

Hawaiian honeycreepers evolved from one common finch ancestor millions of years ago. Some birds, like the ʻiʻiwi, developed long, curved bills to sip nectar out of bell-shaped blossoms, filling their bellies while pollinating the flowers of the forest. Others, like the kiwikiu, developed sturdy beaks to snatch insects from tree bark. The ʻākohekohe, one of the largest honeycreepers, has a feather duster tuft on its forehead and helps spread pollen as it flits from tree to tree. An integral part of native ecosystems, forest birds are important to Hawaiian culture. Kia manu (bird catchers) plucked vermillion and honey-colored feathers for the lei, helmets, and cloaks of Hawaiian royalty. ʻŌlelo noʻeau (Hawaiian proverbs) reference birds in describing love, gossip, industriousness, and beauty. “He kumu lehua muimuia i ka manu,” means an ohia in full bloom attracts forest birds, as an attractive person will bring attention from others.

With the arrival of humans to the Hawaiian archipelago came invasive predators like rats for which native birds had no defense. But the greatest impact on native birds in recent history has been mosquito-borne diseases, primarily avian malaria and avian pox. Out of the 17 honeycreepers that remain, majority are federally endangered or threatened. Kiwikiu and ʻākohekohe populations have decreased by more than 70 percent over the last 20 years. Scientists predict their extinction in two to fifteen years if no action is taken to control mosquitoes in the forest.

A warming climate is allowing mosquitos to now reach high-elevation forest bird habitat. The southern house mosquito is the primary vector of avian malaria and has a 100% transmission rate. Some birds are particularly at risk – just one bite from an infected mosquito can mean death for a vulnerable forest bird. (Photo: Jack Jeffrey)

Mosquitoes, and the diseases they transmit, don’t thrive in colder environments and have historically been restricted to warmer, lower elevations. Unfortunately, a warming climate is allowing these pests to reach high-elevation forest bird habitat, the last refugia. The southern house mosquito is the primary vector of avian malaria and has a 100% transmission rate. Some birds are particularly at risk – just one bite from an infected mosquito can mean death for a vulnerable forest bird.

The southern house mosquito is the primary vector of avian malaria and has a 100% transmission rate. Some birds are particularly at risk – just one bite from an infected mosquito can mean death for a vulnerable forest bird.

The multi-agency Birds, Not Mosquitoes Project is urgently working to save our native honeycreepers from extinction. They have been exploring use of a naturally-occurring bacteria that is present in over half of all insect species worldwide, including many in Hawaiʻi. This bacteria, called Wolbachia, affects mosquito reproduction. Luka Zavas, Outreach Manager with the American Bird Conservancy, one of the agencies involved in the project, explains how it works. “When male and female mosquitoes have matching Wolbachia strains, the sperm and egg are like connecting puzzle pieces that result in fertile eggs. When a male mosquito has a different, incompatible strain than its female mate, their puzzle pieces won’t match, resulting in infertile eggs.”

Wolbachia is a naturally occurring bacteria present in over half of all insect species worldwide, including many in Hawaii, and can be critical to saving Hawaii’s last forest birds. When male and female mosquitoes have matching Wolbachia strains, the sperm and egg are like connecting puzzle pieces that result in fertile eggs. When a male mosquito has a different, incompatible strain than its female mate, their puzzle pieces won’t match, resulting in infertile eggs. — BIRDS, NOT MOSQUITOES PROJECT photo

Researchers hope to save our honeycreepers by raising and releasing male mosquitoes with an incompatible strain of Wolbachia, Swamping the dating pool with unproductive males effectively puts wild mosquito populations on birth control. Repeated releases over time suppress the overall population of mosquitoes and reduce the transmission of avian malaria, with the goal of giving our Hawaiian honeycreepers a fighting chance for survival.

Those working on the project stress that male mosquitoes don’t bite, Wolbachia doesn’t harm people, animals, or the environment, and the process doesn’t modify any genes. The same technique is used elsewhere in the world to control mosquitoes that transmit human malaria.

On Maui, approximately 64,000 acres of federal, state, and privately-managed lands have been identified as a proposed project area for the release of incompatible male mosquitoes. Environmental Assessments prepared for the state and Haleakalā National Park outline the proposed release strategy as well as plans for monitoring mosquito and bird populations to track progress.

For more information on the project, visit birdsnotmosquitoes.org. Luka Zavas will give a community presentation on February 22, 2023, at 5:00 p.m. at the Makawao Public Library. More information can be found here.

Serena Fukushima is the public relations and education specialist for the Maui Invasive Species Committee. She holds a bachelor’s degree in environmental studies and a graduate degree in education from the University of Hawaii at Manoa. “Kia’i Moku, Guarding the Island” is written by the Maui Invasive Species Committee to provide information on protecting the island from invasive plants and animals that threaten our islands’ environment, economy and quality of life.

This article was originally published in the Maui News on February 11, 2023 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

Read more Kiaʻi Moku articles

Prevention Is Key For Maui To Stay Coconut Rhinoceros Beetle Free

Posted on January 31, 2023 by Serena Fukushima

A large, invasive beetle is spreading on Oʻahu. First detected in December 2013 at a golf course near the Honolulu airport, the coconut rhinoceros beetle (CRB) was confined to central and west Oʻahu during the early years of the infestation, thanks to the work of Coconut Rhinocerous Beetle Response – the interagency team that formed to address it. But since the summer of 2022, the project has seen an explosion of detections, with CRB infestations discovered at new locations on the island. The beetles have not been detected on any of the neighbor islands, but it’s likely just only a matter of time before they arrive.

*At 2 1/2 inches long, coconut rhinoceros beetles are nocturnal and can fly up to 2 miles, spending most of their lives hidden high in the tops of coconuts. — Photo: CRB Response*

Coconut palms are the preferred host, but the beetles also live on other palms, banana trees, sugar cane, agave, and even ironwood, taro, and hala. Mature coconut trees can typically withstand feeding damage, but juvenile plants often die. Over time, as mature trees age out, an entire species of palm can disappear. Endangered native palms – loulu – are especially at risk.

At 2 ½ inches long, these large, black beetles are nocturnal and can fly up to two miles, spending most of their lives hidden high in the tops of coconuts, boring into the crowns of healthy palm trees. Adults bore through unopened leaves to feed on the sap. An adult female beetle emerges from the crown to lay up to 140 eggs in its lifetime in nearby mulch piles or decomposed tree stumps. Plump, brown-headed larvae with bluish-grey tails are huge – ranging from two to four inches long.

Through a coordinated partnership with the University of Hawaiʻi, U.S. Department of Agriculture, Hawaiʻi Department of Agriculture (HDOA), and other key organizations, the Coconut Rhinoceros Beetle Response team has been working to stem the tide of this invasive pest on Oʻahu. The team’s multi-pronged strategy includes the placement of pheromone traps, detector dogs, treatment of high-risk materials, quarantine protocols, research, and outreach. Arisa Barcinas is the Outreach Specialist for CRB Response, and champions successful control of CRB. “When green waste is managed properly,” she explains, “It can drastically reduce an infestation and allow damaged palms to grow back.”

Coconut rhinoceros beetles bore into the crowns of healthy palm trees and bite through unopened leaves to feed on the sap. The most obvious sign of this beetle’s presence are bore holes in the crowns of palm trees or V-cut formations in the leaves. — Photo: HDOA

The beetles spread to new places by hitchhiking in the holds of aircraft and through movement of nursery stock, compost, and mulch. To contain the beetle and prevent its spread to other islands, HDOA declared Oahu a CRB quarantine zone. Businesses must complete a series of steps before moving high-risk material, like mulch or host palms. Before being shipped, HDOA inspects and treats the material using high heat or fumigation. If beetle damage is detected, plants don’t move. Plants and materials are inspected again at their destination to ensure there are no hitchhikers.

Early detection efforts have been in place to prevent the spread to other islands. The Maui Invasive Species Committee’s (MISC) Early Detection team conducts regular surveys for CRB. Staff on Maui and Molokai (Molokai Invasive Species Committee) monitor traps at the airport twice a month.

Prevention and reporting are critical to catching this pest early. Barcinas says, “It’s important to understand how devastating CRB can be if it spreads to other islands. Community involvement is crucial to prevent the establishment of this pest in other places.” Her team has been increasing its work on neighbor islands by installing more traps and coordinating logistics to bring over detection dogs for surveys.

Invasive species committee staff on Maui and Molokai monitor coconut rhinoceros beetle traps at the Kahului Airport twice a month. The beetle is only found on Oahu, and prevention and reporting are critical to catching this pest early should it reach Neighbor Islands. – Photo: Forest and Kim Starr photo

The most obvious sign of this beetle’s presence are bore holes in the crowns of palm trees or v-cut formations in the leaves. Using mulch and compost right away by spreading it thinly, rather than storing it in piles, is another way to prevent beetle breeding habitat and undetected infestations. Suspect CRB on Maui should be reported immediately to 643pest.org. Make sure to upload a photo of the beetle and/or signs of damage and note the exact location in the report. A pest prevention training describing CRB and other invasive species is offered to nurseries and can be found at plantpono.org. More information about this pest and compliant businesses on Oʻahu are at crbhawaii.org.

This article was originally published in the Maui News on January 14, 2023 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

Read more Kiaʻi Moku articles

Invasive species can cause native ecosystems to go up in smoke

Posted on January 31, 2023 by Serena Fukushima

In early November, a wildfire ripped through nearly 2,100 acres of parched land in West Maui. The fire blazed across the landscape, then quickly moved upwards through one of the last and highly diverse native ecosystems left on Maui, destroying some of the last remaining endangered flora and fauna on earth. Unlike many forests around the world that depend on wildfire, Hawaiian forests are not adapted to wildfire cycles (The only natural wildfire occurrence in our islands happens around volcanic events). and are slow to recover after a fire event. Where once an ecologically diverse environment thrived, invasive species quickly move in.

Mauna Kahālāwai Watershed Partnership aerial surveys reveal the devastation of the November fire in West Maui. This photo shows the stark contrast between burned forest and kipuka that evaded the blaze. Crew members are navigating logistics to safely land to do ground surveys to determine the extent of the damage to rare native forest in this area. — Photo: Mauna Kahālāwai Watershed Partnership

Most of Hawaii’s fire zones were once home to diverse native dryland forest. Since the introduction of invasive ungulates and plant species, over 90% of the original Hawaiian dry forests have been destroyed across the state. When the forest disappeared, introduced, invasive grasses adapted to fire moved in. Melissa Chimera, Pacific Fire Exchange Coordinator for the Hawaii Wildfire Management Organization notes that Hawaii has one of the largest footprints of wildfire impact per landmass in the United States. “With the decline in agriculture around the state, large swaths of abandoned farm lands were replaced with fire prone invasive grasses,” Chimera says, “Grasses like guinea grass and fountain grass (found on Hawaiʻi Island) create a fire cycle, quickly burning then reestablishing in the bare ground.” Not only does fire affect people and native forest, but runoff from bare ground post fire moves into oceans, smothering coral reefs. Chimera also notes that the latest predictions for Hawaiʻi is expecting some of the most drastic effects of the climate crisis by mid-century. Heavy rains, followed by prolonged drought, creates an increased fire risk as well- boosting growth of invasive grasses which then dry up and become fire starters at a landscape level. Areas like Lāhainā, dominated by these invasive grasslands, are an example of one area caught in the fire cycle.

Kim Thayer, Program Associate with the Mauna Kahālāwai Watershed Partnership, works in some of the last dryland forest found in West Maui. Already battling invasive ungulates looking to feast on these precious plants, climate change induced drought has quickly dried up the area. Thayer notes, “Before the fire, it was so dry. Even the aalii, one of our most resilient native plants, was crispy.” When the fire took off, legs of it raced 4,500 feet to the peak of Helu, a steeply cliffed slice of land south of Kauaʻula Valley. “There is an assemblage of plants that are so specific to that place, they don’t exist anywhere else on the mountain, let alone the world”, Thayer says of Helu. The names of extremely rare species such as Cyanea heluensis and Stenogyne kauaulaensis lend to how specific these plants are to this area. While the earth was still smoldering, her team did an aerial survey to get an idea of the extent of the burn. Thayer laments, “The forest burned down to the ground in some of the places.” As of publication of this article, it was too ashy for the helicopter to land safely to do a boots on the ground survey to survey the extent of the damage and what was lost, but the outcome is looking grim.

Stenogyne kauaulaensis is one of the critically endangered species found in an area of West Maui hosting some of the last native dryland forest on the island. It is unknown how many species were lost when the November wildfire blazed through this precious swath of forest. Pictured is a 2010 photo of nursery-cultivated Stenogyne kauaulaensis slated for restoration efforts. — Photo: Forest and Kim Starr

When native forest is burned, there is a possibility of regrowth from an established seed bank or older trees. But invasive grasses grow faster, and outcompete the slower growing natives in an area. The added pressure from feral pigs and axis deer create a disastorous recipe for native forest resilience after repeated fire pressure.

As we move into climate change induced weather events, including wildfires, Chimera encourages people to take action. “The time to prepare for a wildfire is not when the fire is moving your way, but now”. She recommends several ways to get fire ready: Keeping access open for emergency personnel, clearing excess vegetation around your home, and using fireproof materials (like metal roofs) to harden your home. A plethora of resources and research can be found at pacificfireexchange.org.

A wildfire scorched nearly 2,100 acres of West Maui in November. Areas like Kauaʻula and Helu are home to some of Maui’s last native dryland forest ecosystems. Native species are generally not adapted to wildfire, and invasive grasses colonizing the bare ground will inhibit full recovery of the dryland ecosystem. Rare native species such as Stenogyne kauaulaensis and Cyanea heluensis call these high mountain peaks home and are found nowhere else in the world. — Photo: Mauna Kahālāwai Watershed Partnership

As for restoration efforts in Helu, Mauna Kahālāwai is still assessing the damage and navigating complicated logistics to access the isolated peak. Looking ahead, Both Chimera and Thayer believe that landscape level invasive grass control is key to reducing wildfire occurrences. Mauna Kahālāwai Watershed Partnership has been working in Olowalu Valley in partnership with Kīpuka Olowalu to create a native plant green belt with the goal of planting 1,000 plants to restore the riparian corridor and help with fire suppression. A few valleys down, Keʻeaumoku Kapu, a resident of Kauaʻula Valley, has been organizing a similar project to restore the charred earth with lush native species. Find out more and how to volunteer with both groups at www.maunakahalawai.org and by emailing Kapu at kapukapuakea@gmail.com.

This article was originally published in the Maui News on December 10, 2022 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

Read more Kiaʻi Moku articles

The Sweet History of ʻUala: A Staple Food to Give Thanks For

Posted on November 15, 2022 by Serena Fukushima

A year-round staple in our islands will soon take center stage on many Thanksgiving dessert tables. The sweet potato is often overlooked, with favor leaning towards the more popular pumpkin pie. Still, its origins weave a fascinating history which include Poynesian voyagers, territorial farmers, invasive species, and celebration of African American culture . Follow the journey of this humble root in Hawaii and beyond.

The sweet potato (Ipomoea batata) is a part of the morning glory family and can grow from sea level to over 2,000 feet. The root (potato) is high in carbohydrates, beta-carotene, and vitamins, and the edible leaves are high in protein, making it an ancient and modern-day superfood. It grows in a variety of soils and withstands drought, making it a staple in ancient Hawaiʻi. Hawaiians had developed over 250 varieties of sweet potato- ʻuala in Hawaiian- which ranged in color from yellow, orange, red, purple, and white. Its importance is emphasized in the ʻŌlelo Noʻeau (Hawaiian proverb) “He ʻuala ka ʻai hoʻola koke i ka wī (The sweet potato is the food that ends famine quickly). But how did uʻala get here?

Using DNA analysis, French researchers from the Center for Functional and Evolutionary Ecology found that Hawaiʻiʻs sweet potato originated high in the South American Andes mountains. To get an accurate sample of pre-contact potatoes, they analyzed the dried remains of ʻuala from Captain James Cook’s voyages in 1796. They traced the genetic blueprint of these samples to Ecuador and Peru. In addition to indigenous, archaeological, and linguistic knowledge, ʻuala’s genetic evidence showed that Polynesian voyagers interacted and traded with natives in South America. After the Hōkūleʻa’s worldwide voyage from 2013-2018, the ability of ancient Polynesian voyagers to make a trip like this was no longer up for debate; however, the humble sweet potato offers further evidence that these highly skilled ancient wayfarers were able to make a journey of this magnitude.

Hawaiians had developed over 250 varieties of sweet potato- ʻuala in Hawaiian- which ranged in color from yellow, orange, red, purple, and white. By 1923, only 70 known species remained. Today, there are only about 24. Photo: Serena Fukushima

ʻUala was an essential famine food and crop in ancient Hawaiʻi but was also significant to modern economies. Commercial cultivation of sweet potatoes first began in 1849. In 1919, it was grown as one of the top ten emergency foods during the World War (replacing white potatoes and used as livestock feed). But, despite being extensively cultivated in Hawaiʻi, the ancient Hawaiian varieties were being lost. By 1923, only 70 known species remained. Today, there are only about 24.

By the 1990s, just over 1,000 acres of sweet potato were in cultivation in Hawaiʻi, generating over $7 million for the economy. In 2016, farmers had less than 500 acres in sweet potato statewide, generating just under $2 million.

The reason why? Pests – primarily sweet potato weevils. These ½ inch, ant-looking insects are the most significant pests to sweet potatoes worldwide. The larvae channel the potato roots, and high concentrations can result in hundreds of larvae feeding on just one potato. This makes the potato unmarketable and inedible (the root becomes bitter in response to the pest damage). Sweet potato weevils are not the only potato plagues- the sweet potato bug, leaf miners, vine borers, hornworms, and nematodes are others. There is hope though. Researchers at the University of Hawaiʻi at Mānoa have recently discovered two Hawaiian varieties showing promising results in flavor, yield, and pest resistance. Perhaps the sweet potato may become an agricultural staple in Hawaiʻi yet again.

Commercial cultivation of sweet potatoes has been an important part of Hawaii’s agriculture economy since 1849, however, by 2016, farmers had less than 500 acres of sweet potato in cultivation statewide. Photo: Forest and Kim Starr

As a staple on the holiday dinner table, sweet potato pie is widely beloved. Although indigenous peoples cultivated sweet potatoes in the Pacific and the Americas centuries before the first Thanksgiving, sweet potato pies as a holiday tradition stems from Southern plantation kitchens, baked by enslaved African Americans. After emancipation, recipes followed freed peoples throughout the country, remaining a holiday favorite in African American communities today. But the love of sweet potato pie reaches far and wide and has made its way back to Hawaiʻi. Try this tropical twist on the traditional sweet potato pie this Thanksgiving: a Sweet Potato Haupia Bars recipe by Maui-based Instagram and YouTube cooking star Relle Lum (@keeping.it.relle) at keepingitrelle.com/sweet-potato-haupia-pie-bars.

This article was originally published in the Maui News on November 12, 2022 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

Read more Kiaʻi Moku articles

Citizen Science Can Help Stop the Ant

Posted on November 15, 2022 by Serena Fukushima

Citizen scientists have been key to finding most of the little fire ant (LFA) populations on Maui. Without their reports, Maui likely would not have a chance to stop this destructive ant from taking over our island. Ant submissions from concerned residents have also been key to understanding which species are already on the island. In order to understand Maui’s ants better, Monte Tudor-Long, Little Fire Ant Crew Member with the Maui Invasive Species Committee (MISC) compiles records of ants collected through MISC surveys and community reports. “MISC has collected over 40 species of ants- just about every ant known to exist on Maui.” Tudor-Long says.

October is Stop the Ant Month, a statewide initiative bringing awareness to little fire ants and other harmful ant species. Folks who submit ant collection kits to MISC during October will be entered into a raffle to win prizes all month long! Photo: MISC

All the ants in Hawaiʻi are thought to have been brought here by humans. Over 60 species are now present. Ants are considered “ecosystem engineers” altering soils, nutrient cycling and decomposition, and food chains. They are effective and aggressive predators. Here in Hawaiʻi, many have become invasive, causing harm to the animals not evolved to defend themselves against non-native pests.

Tudor-Long believes that identifying Maui’s ants can lead to the early detection of harmful, new species. “If every household on Maui sent in samples of their ants, it would create a citizen science-based research repository that could help inform future conservation decisions,” he says. Public submissions can help find new ant species not yet known to be in Hawaiʻi. They are also vital in detecting new little fire ant populations, a MISC target because of the harm they cause. In fact, 13 of the 19 existing LFA infestations were reported by the community.

Tudor-Long encourages folks to observe the ants around them and send them to MISC (request a free collection kit at stoptheant.org). He’ll reply with the identification of the ant, and if LFA is detected, MISC will control the infestation. October is also Stop the Ant Month, and folks who send ants to MISC this month are entered into a raffle to win prizes. Here are some common ants that Maui residents may see and some invasive ones that Maui has a chance to stop:

Observing and collecting the ants around you can help prevent harmful, invasive ants like the little fire ant on Maui or red imported fire ant (not yet in Hawaii) from becoming established in our islands. Both of these ants are target species for the Maui Invasive Species. If you suspect these ants in your area, request a free ant collection kit at stoptheant.org or report to (808) 573-6472. Photos: Alex Wild

Target Ants- Report to MISC at (808) 573-6472
The little fire ant (Wasmannia auropunctata) or LFA damages economies, harms native wildlife, pets, and livestock, and prevents people from spending time outside. The only way to confirm the identification of LFA is by examining them under a microscope. The ant’s venom, which is delivered by multiple stings at once, leads to an itchy, burning sensation that can last for hours or even days. LFA are slow-moving and unaggressive. This arboreal ant literally rains down on people as they brush past infested foliage. LFA are not widely established on Maui and should be reported to MISC.

The red imported fire ant (Solenopsis invicta) or RIFA has not been detected in Hawaiʻi and should be reported to MISC. Plaguing the southern United States, RIFA are exceedingly aggressive, attacking with painful stings. The hope of controlling and eradicating this ant will require early detection of its arrival. Says Tudor-Long, “If it arrives under the radar and we fail to notice right away, it will spread rapidly throughout the drier, sandy lowlands of Maui.” For this reason, samples of tropical fire ants, a lookalike species, should be routinely collected and sent to MISC to make sure it is not RIFA.

All the ants currently in Hawaiʻi are thought to have been brought here by humans, and over 60 species are now present. The Hawaiian carpenter ant, tropical fire ant, and African big-headed ant are all common species that most people see in their homes or yards. Photos: Alex Wild, Melody Euaparadorn (Carpenter Ant)

Common Ants on Maui- Not controlled by MISC:
The Hawaiian carpenter ant (Camponotus variegatus) is the largest ant in the state- up to half an inch long. Winged males and females fly when mating, often swarming toward lights. They are nocturnal, do not sting, and mostly leave people alone. The Hawaiian carpenter may nest in wood cavities but does not damage wood. Carpenter ants are one of the first ant species ever documented in the islands, first recorded by entomologists in 1879.

Tropical fire ants (Solenopsis geminata) have been tormenting beach-goers in Hawaiʻi since the mid-1800s. These aggressive ants sting the feet and ankles of any passerby near their nests. Tropical fire ants are red and can reach up to a third of an inch. Compared to little fire ants, these ants are gigantic – up to four or five times the size of LFA. Slow-moving LFA are nearly invisible, while fast-moving Tropical Fire Ants are quite easy to see swarming on your bare feet.

The African big-headed ant (Pheidole megacephala) was one of the first ants to be introduced here. By the late 1800’s it wiped out scores of endemic insect species as it mowed its way through Hawaiʻi’s native forests. You can find these ants just about everywhere in Hawaiʻi up to around 3,000 feet elevation. They bite our legs and feed on non-native insects like the larvae of houseflies. This species makes small ant hills – and ant “roads” – especially after heavy rains.

This article was originally published in the Maui News on October 8, 2022 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

Read more Kiaʻi Moku articles

New training helps nurseries be on the lookout for invasive species

Posted on November 15, 2022 by Serena Fukushima

Hawaiʻi is home to plant and animal species found nowhere else. For millions of years, new arrivals would establish in our islands an average of once every three thousand years via makani (wind), moana (deep ocean currents), or manu (birds or seeds hitchhiking in their gut). After they arrived to our isolated island chain, they evolved to live in their new environment, becoming new species over hundreds of thousands of years. Today, due to globalization, a new plant, animal, or pathogen that has never been documented in Hawaii arrives every three days. Some of these new arrivals can become invasive, harming not only our environment and Hawaiʻi’s unique biodiversity but also causing adverse effects on our agriculture industry, health, cultural practices, and quality of life.

Multiple agencies across the state work every day to address invasive species issues and local businesses are pitching in. Since many new species arrive hitchhiking on nursery materials, nurseries can be front-line heroes in helping to stop new pests before they spread into the environment.

A new training for nurseries is now available. The Pest Prevention Training Program was created by a grant from the United States Department of Agriculture Animal and Plant Health Inspection Service. The training, offered by the island-based Invasive Species Committees, will feature information about the identification, reporting, and best management practices for some high-risk pests that are either not known to occur in Hawaii, not known to occur in the United States, or pests that are present but are a high priority for containment (like coconut rhinoceros beetle)

Here are some pests not yet found on Maui to be on the lookout for. If you think you’ve seen these pests, report immediately to 643pest.org:

The Pest Prevention Training Program is a new training for nurseries across the state to detect and protect Hawaiʻi from invasive species. The training will feature information about the identification, reporting, and best management practices for some high-risk pests that are either not known to occur in Hawaiʻi, not known to occur in the United States, or pests that are present but are a high priority for containment. Some of the pests not known to be in Hawaiʻi that will be covered in the training are featured (from top left to right) milk snail, citrus greening effects on fruit, brown marmorated stink bug, lethal palm yellowing, northern giant hornet, black velvet leatherleaf slug, and red imported fire ant. Photos (in order): Bugh, Lotz, Ellis, Harrison, Alpsdake, Cranshaw, and Noble.

Coconut Rhinoceros Beetle
Currently only found on Oahu, the coconut rhinoceros beetle (CRB). Adults are long (up to two inches), shiny black in color, with a single horn. CRB are nocturnal and can fly. They are primarily found in decomposing green waste or in the crown of palms, where they leave oval-shaped boreholes midrib of fronds or in the crown or trunk of the tree. Fronds cut in a V-shape pattern are another indication of CRB presence. They have also been found in hala trees in Hawaiʻi and can threaten rare native Hawaiian palm species. Extensive damage can kill trees.

Citrus Greening
Citrus greening is bacteria that affect citrus’s vascular system and nutrient uptake. Though not detected in Hawaiʻi, the primary vector, the Asian citrus psyllid, is present in our islands. Throughout the world, the arrival of the Asian citrus psyllid has been followed by the detection of this disease-causing bacteria. This bacterium is responsible for the loss of millions of acres of citrus in the US and beyond. In Florida, citrus greening resulted in 8,000 lost jobs with an economic impact of $4.5 billion. Today, Florida’s citrus industry covers half the acreage it once did. Symptoms include lopsided, bitter, hard fruit with tiny, dark seeds, blotchy mottling on leaves, and fruit that remains green even when ripe.

Red Imported Fire Ant
The Red Imported Fire Ant (RIFA) is an aggressive ground-dwelling ant known for its painful stings. RIFA has resulted in a $1 billion impact in the United States alone. Native to South America, it is a serious pest across the continental U.S. but has not yet been detected in Hawaiʻi. Similar in size and behavior to the well-established tropical fire ant, members of the public are encouraged to submit samples of any stinging ant to their local invasive species committee to prevent an unknown infestation of RIFA from becoming established. Request a free ant collection kit at stoptheant.org.

Lethal Palm Yellowing
Lethal palm yellowing is caused by a bacterial parasite that lives within the plant’s vascular system. This disease affects at least 37 palm species and is responsible for wiping out the majority of the tall-type coconut cultivars in Jamaica and Florida. It can take three to nine months before symptoms are apparent, including yellowing of the leaves and premature dropping of fruit.

Local nurseries can learn more about the Pest Prevention Training as well as the full list of pests to be on the lookout for at plantpono.org/pest-training.

This article was originally published in the Maui News on September 10, 2022 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

Read more Kiaʻi Moku articles

The Hawaiian Crow May Soon Soar on Maui

Posted on November 15, 2022 by Serena Fukushima

One of the rarest birds in the world may soon fly through the remote, forested slopes of Maui. The ʻalalā, or Hawaiian Crow, is endemic to our islands, but due to impacts from introduced predators (such as cats and mongooses), loss of habitat, and diseases, they are now extinct in the wild. Just over 100 individuals are all that remain in the world, raised in conservation breeding facilities on Hawaiʻi Island and Maui. The latest efforts to reintroduce birds to the wild on Hawaiʻi Island took place between 2016-2019. The birds suffered low survival rates after release, which led scientists to pause the program. On Hawaiʻi Island, ʻalalā has a native predator- the ʻio, or Hawaiian hawk. There are no breeding populations of ʻio on Maui, so conservationists believe that the Valley Isle could serve as the next step in the recovery of the endangered Hawaiian crow.

The Hawaiian Islands were home to at least five different native crow species. ʻAlalā (Corvus hawaiiensis) are the only ones that remain, and the last wild individuals were observed by researchers on Hawaiʻi Island in 2002. Subfossil records indicate that at least one variety of these Hawaiian crows was present on Maui, Molokaʻi, and Oʻahu.

The last wild Hawaiian crows were spotted on Hawaii Island in 2002, however subfossil records show they were once prevalent on Maui. Remaining ʻalalā are in conservation breeding facilities, and reintroduction efforts on Hawaiʻi Island have been complicated by introduced predators, diseases such as toxoplasmosis, and a native hawk predator. Maui lacks populations of native hawks, and could soon be a viable home to these endangered species. Photo Credit San Diego Zoo Wildlife Alliance

Sarah Malick-Wahls is the Maui Nui ʻAlalā Research and Recovery Coordinator with the Maui Forest Bird Recovery Project. Her team is looking at remote, native forested areas on Maui to release captive-bred birds. She explains, “ʻAlalā thrive in ohia dominant forests, and multiple Maui sites have the potential to host this endangered species once again.”

ʻAlalā have a varied diet- they eat invertebrates, eggs, and nestlings of other forest birds, nectar, and carrion- but their diet of native fruits made them an integral part of a native forest ecosystem as seed dispersers. Indulging in over 30 varieties of native fruiting plants, ʻalalā could contribute to restoring diverse native forests that benefit the watersheds, cultural practices, and unique plants and animals that inform Hawaiian culture. Intelligent and vocal, alala form complex social relationships with human-like calls. One translation of ʻalalā means to “bawl, caw, wail, scream, etc.” which perfectly describes the sound of their cacophonous symphony.

Reintroduction efforts to bring back the call of ʻalalā to Hawaii Island forests have been complicated. Introduced predators such as mongooses, rats, and cats have greatly impacted ʻalalā survival, especially fledglings that spend time on the ground while learning to fly. Some crows have even contracted toxoplasmosis transmitted from feral cats, which is still a concern for future release efforts. While Hawaiʻi Island reintroduction efforts are on pause, conservation breeding facilities are running out of space to house the entire population of ʻalalā, so conservationists are thinking creatively about reintroducing Hawaiian crows to their former homes on other islands. Multiple ʻalalā populations in separate locations also help ensure the species’ survival in the event of extreme weather instances (like hurricanes) or other unforeseen circumstances that could threaten this critically endangered species.

ʻAlalā eat invertebrates, eggs, and nestlings of other forest birds, nectar, and carrion- but their diet of native fruits made them an integral part of a native forest ecosystem as seed dispersers. Intelligent and vocal, ʻalalā form complex social relationships with human-like calls. One translation of ʻalalā means to “bawl, caw, wail, scream, etc.” which perfectly describes the sound of their cacophonous symphony. Photo Credit DLNR/DOFAW

“The reintroduction of ʻalalā to Maui could contribute not only to the survival of this species but can help revitalize and restore native forests.” Malick-Wahls explains. Along with her team, she’s held meetings with communities in East Maui–one of the potential release areas–to share the proposed plans. “So far, community input has been overwhelmingly positive.”Malick-Wahls says.

Her team will incorporate comments from the initial community meetings into a release plan for draft environmental and cultural assessments. These drafts are projected to be ready this winter for broader public commenting. If all goes well, the forests of Maui may once again be filled with the distinctive call of this treasured native species in its forests after hundreds of years of silence.

This article was originally published in the Maui News on August 13, 2022 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

Read more Kiaʻi Moku articles

Coconut palms are woven into the culture of the islands; a beetle threatens that connection

Protecting ‘Ōhi‘a: Fencing for the Trees

Is ant-watching really a thing?

The race to protect Hawaii’s native forest birds from extinction

Prevention Is Key For Maui To Stay Coconut Rhinoceros Beetle Free

Invasive species can cause native ecosystems to go up in smoke

The Sweet History of ʻUala: A Staple Food to Give Thanks For

Citizen Science Can Help Stop the Ant

New training helps nurseries be on the lookout for invasive species

The Hawaiian Crow May Soon Soar on Maui

Get Involved

Sign up for MISC Updates

Contact Us