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

Illegal dumping poses risk for the spread of invasive species

Posted on July 31, 2020 by Lissa Strohecker

Little fire ants are another invasive pest that is known to spread through the movement of green waste and debris. Green-waste facilities are monitored for these pests to reduce the risk of spread but illegal dumping can circumvent these safeguards. — Maui Invasive Species Committee photo.

The evening of July 24, 2018, a Maui resident living near the Five Corners area of Haʻikū heard something she did not recognize as a normal sound for her neighborhood: the 2-note call of invasive coqui frogs. “I was in shock,” she says. “All the sudden there were 5-10 coqui frogs near my house.” She reported the frogs to the Maui Invasive Species Committee (MISC) and worked with neighbors to pinpoint the frogs’ location in a gulch adjacent to a nearby pasture.

When crews arrived a few days later, they indeed found coqui frogs spread across a quarter acre. They also found a rubbish pile with tires and plywood. “Given that there were no frogs, then suddenly ten—that’s too many to have jumped onto a car and been moved to the site,” explains Abe Vandenberg, MISC Coqui Coordinator. “The more likely scenario is that there was a clutch of eggs moved in the rubbish pile.” Coqui frogs hatch out from their eggs as tiny froglets, unlike other frogs that go through a tadpole stage that requires standing water.

“They reach unnaturally high densities that are 2-3 times higher here in Hawaiʻi than in their native habitat.”

Coqui are an introduced species to the Hawaiian Islands. Without the predators like snakes that keep them in check in Puerto Rico, they reach unnaturally high densities that are 2-3 times higher here in Hawaiʻi than in their native habitat. In turn, they impact insect populations and nutrient cycling. But their mating call is what drives control efforts – males call “co-qui” from dawn until dusk in a piercing cacophony that disrupts sleep.

Unfortunately, the Five Corners situation is not unique. Even in the early days of coqui control efforts on Maui, roadside dumping factored into the amphibians’ spread. A vehicle abandoned in Māliko Gulch was the likely vector of frogs to a salvage yard in Haʻikū. As the coqui population increases on Maui, so do the instances of coqui moving in green waste and trash. In the last year, illegal dumping has been the vector for at least five introductions of coqui that MISC is aware of. More often than not, the frog-infested trash is dumped in gulches – a difficult and dangerous place for crews to access and remove the noisy invaders.

Coqui frogs, like this male guarding his eggs, take advantage of man-made materials for shelter. Illegally dumping rubbish can spread pests like coqui and make removing them more difficult. — Maui Invasive Species Committee photo

It’s not just coqui frogs hitchhiking in trash and yard waste. On Hawaiʻi Island and in Tahiti and Guam, little fire ants have been spread through green waste. On Maui, MISC has worked with the owners of properties infested by little fire ants to address this threat, but undetected populations of pest ants most likely still exist. On Oʻahu, the larvae and eggs of the palm-killing coconut rhinoceros beetle (CRB) develop in coconut mulch, so preventing the spread of green waste is the most important task for crews working on the CRB Response Team. Coconut Rhinoceros Beetles are killing coconuts and other palms on Oʻahu and have not yet been reported from other islands.

Coconut Rhinoceros Beetles lay eggs in mulch so stopping the movement of infested debris is a priority for the CRB teams on Oahu. — U.S. Army Garrison Hawaiʻi photo

When yard clippings and mulch are properly handled, green waste is less of a threat. The temperature of a managed compost pile reaches 150 degrees Fahrenheit, enough to kill weed seeds and many invasive pests and eggs. Additionally, bringing green waste to a central location allows for monitoring. Green waste sites on Maui are regularly surveyed for the presence of little fire ants.

People who are tempted to dump their rubbish illegally may not realize that the impacts of their actions can be catastrophic. Often, illegal dumping attracts more dumping. The tangle of trash provides ample sites for pests to hide out and avoid treatment. You can help. Properly dispose of waste at the landfill, green waste facility, or compost it on site. Report illegal dumping to the Maui Police Department, at (808) 244-6400, and to the State of Hawaiʻi Department of Health at (808) 984-8230.

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 August 12th, 2018, as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

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Removing invaders can help decrease damage from hurricanes

Posted on July 23, 2020 by Lissa Strohecker

Floodwaters from Hurricane Harvey spread living rafts of red imported fire ants in Texas. While Hawaiʻi does not have red imported fire ants, storms and floods can help to spread other species that are present such as the little fire ant. — BRAND KELLY / Wikimedia Commons photo.

Hurricane Harvey didn’t just bring floodwaters to Texas; it also spread a plague of stinging ants.

Red imported fire ants are highly aggressive pests that have invaded the southern United States. These ants are particularly adept at surviving floods – a strategy they developed in the wetlands of their native Brazil. When their nests become waterlogged they form rafts, clinging to each other to stay afloat as floodwaters carry them elsewhere. When they make landfall they set up a new home – but landfall for a floating anthill could be a paddle or a rescue skiff leaving the passengers battling swarms of stinging ants. After Hurricane Harvey, pictures of the rafting ants filled the news. Twice Hawaiʻi inspectors have intercepted these ants in shipments bound for the Aloha State, but as far as we know this painful plague has not yet established itself in the Islands.

Fire ants aren’t the only nuisance species spread by hurricane winds and associated flooding.

In 1992, Hurricane Andrew hit Homestead, Florida. The intense winds flattened a reptile collector’s greenhouse, sending baby Burmese pythons flying through the air. Homestead borders Everglades National Park. While most of these airborne serpents probably died, scientists suspect some survived and likely reinforced the existing population of escaped reptiles. Pythons are now one of Floridaʻs biggest pests, both in size and impact. A full-grown python can be 20’ in length and these giants threaten the survival of the endangered Florida panther and other unique wildlife.

Resource managers in Hawaii are worried about a much smaller pest traveling on the winds of hurricanes and storms. Spores from the fungus responsible for Rapid ʻŌhiʻa Death, the disease that has killed ʻōhiʻa trees across 75,000 acres of forest on Hawaiʻi Island, is wind-dispersed. High winds can knock off branches and wound a ʻōhiʻa tree, opening up a site that’s vulnerable to infection—similar to how a wound on your skin exposes you to infection. Rapid ʻŌhiʻa Death was recently discovered in Kohala in September of 2017, only 40 miles from Maui – easily within the distance of a windstorm. Resource managers are increasingly worried that Maui’s native forests could be next.

Albizia trees took a hit in 2014 when Tropical Storm Iselle made landfall on Hawaii island. The damage from these invasive trees falling on power lines and roads took weeks to clean up. — U.S. National Guard / Wikimedia Commons photo.

Intense storms can also damage an otherwise intact rainforest, rendering the forest ecosystem more vulnerable to invasive plants. Hurricanes and storms can fell big canopy trees, opening up a gap that gives a fast-growing invader the light and space it needs to get a foothold. Many of those invaders are shallow-rooted and conducive to landslides, exacerbating the problems hurricanes cause.

Exotic species and the altered forest that they form may not be able to weather the winds as well as an intact rain forest. Storm impacts are amplified as a result. In 2014, Tropical Storm Iselle struck areas of Hawaiʻi Island where albizia trees dominated the landscape. These invasive giants fell hard, taking down power lines and blocking roads. The clean-up took months; albizia became a poster child for invasive species problems.

The onset of climate change underscores the importance of bolstering the health of our rainforests. Tropical ocean temperatures are expected to increase and with that rise comes more intense storms and hurricanes. Considering widespread invasive plants established at lower elevations, increasing storms could lead to a cycle of increasing forest destruction which will lead to drastic changes in forest canopy structure and composition.

While we can’t control the weather, we do have control over the choices we make in our daily lives and the causes and programs we support. Efforts to eradicate or contain invasive species are important to help the rainforest retain resilience to storms and preserve our quality of life.

You can help by using non-invasive plants in your landscaping, plants that will not exploit the damage caused by tropical storms, and keeping an eye out for invasive species like fire ants. Avoid the temptation to plant fast-growing, exotic trees. Support organizations dedicated to protecting our islands from invasive species. For the long term, support policies and programs that will reduce our carbon footprint and promote sustainability. Our individual actions do make a difference—just about any effort is worth the trouble if we can avoid rafting ants and flying snakes.

This article was originally published in the Maui News on October 8th, 2017, as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

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Coqui frogs negatively affect the environment in more ways than one

Posted on June 18, 2020 by Lissa Strohecker

Coqui have the perfect environment in Hawaiʻi, one that lacks the predators – lizards, tarantulas, and snakes- found in their native Puerto Rico. They reach densities two to three times greater in Hawaiʻi than in Puerto Rico, the densest population of land-living amphibian known anywhere. — Maui Invasive Species Committee photo.

In the dark, Darrel Aquino turns off the pump engine – the silence is a stark contrast to the noise of the gasoline motor, and before that, the piercing calls of the coqui frogs that met Aquino and his crew from the Maui Invasive Species Committee when they arrived hours earlier. They work together to pack up, rolling up fire hose by the light of headlamps before heading back to the baseyard. They’ll be back out tomorrow, and the night after, but in a different area of Haʻikū, as they work to stop the spread of the coqui frog.

From dusk to dawn males call for mates, “Co-qui, co-qui.” The first note, “Co,” lets their competition (other male frogs) know they are there, and the “qui” is for the girls. As loud as a lawnmower or leaf blower, the calls drown out the sounds of a night in Hawaiʻi: crickets, the night breeze rustling leaves, waves breaking along the coast.

But while the ear-splitting call of this tiny tree frog is what they are famous for, problems with the coqui frog goes beyond noise. Like us, these invasive frogs from Puerto Rico also find our island habitat and climate to be paradise. Coqui in Hawaiʻi reach population densities greater than any terrestrial amphibian species elsewhere in the world. At over 20,000 frogs per acre in an environment that evolved without frogs, there is bound to be an impact.

“Coqui in Hawaiʻi reach population densities greater than any terrestrial amphibian species elsewhere in the world. At over 20,000 frogs per acre in an environment that evolved without frogs, there is bound to be an impact.”

Dr. Karen Beard, a professor at Utah State University, and her students have studied coqui frogs in the Islands for more than a decade. The interactions between invasive species from different parts of the world coming together in a new environment can be hard to predict, but her research is finding that the presence of coqui in Hawaiʻi tends to benefit other introduced species – from invasive plants to non-native birds to mongoose.

Coqui frogs alter the way nutrients cycle in the ecosystem. The frogs feed on insects, mainly ants, roly-polies, cockroaches, and earthworms, but not mosquitos. What goes in must come out and hundreds of thousands of invasive frogs contribute additional nitrogen and phosphorus to the soil. Though these additions help plants grow, the increase really only benefits introduced plants. The flora native to the Hawaiian Islands is adapted for nutrient-poor volcanic soils, so by increasing soil nutrients, the coqui frogs modify conditions to favor invasive plants such as strawberry guava (native to Brazil).

Coqui frogs also bolster populations of non-native birds. Beard found that populations of some introduced songbirds, including common myna, Chinese hwamei, and red-billed leiothrix (all from Asia), are higher where coqui frogs are present. This is likely due to changes in the insect community when coqui are present (more excrement and frog bodies means more flies) as well as birds consuming the eggs in addition to juvenile and adult coqui.

Mongoose (from India) may also benefit from coqui. Beard’s graduate student Shane Hill looked at rat and mongoose densities where coqui are present compared to where they are absent and found greater mongoose abundance with coqui present. Mongoose are the main scavengers of coqui frogs, which may provide a novel food source. Hill also concluded that increased numbers of non-native birds or coqui-induced habitat changes could favor mongoose.

An invasive mongoose thriving off the abundance of the coqui frog population while increasing the likelihood of predation to other native Hawaiian species. — photo courtesy of Karen Beard

Hill’s study also showed fewer rats where coqui are present, more so for Pacific rats, which den underground as opposed to the more arboreal black rats. Hill and Beard suggest lower rat abundance could result from competition with coqui for insects or increased predation by mongoose. While the relationships are complex, one thing is clear: more mongoose is not good for ground-nesting birds, such as the ʻuaʻu kani (wedge-tailed shearwater) or endangered ʻuaʻu (Hawaiian petrel), and coqui could indirectly contribute to a decline in these birds.

Humans may adapt to the noise of coqui but the environment may be forever changed by their presence; interactions among these invasive frogs and other introduced pests tend to compound the impacts. It’s critical to do what is possible to keep these invasive pests out of the native-dominated areas of Hawaiʻi and sensitive bird habitat.

You can help stop the spread of coqui on Maui. If you have coqui, volunteer in your neighborhood to reduce coqui and remove frog-friendly habitat. If you don’t have coqui in your area, stay alert to any nighttime “Co-qui” calls and report it to MISC at 573-6472.

This article was originally published in the Maui News on February 10th, 2019 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

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Measuring the impacts of invasive plants in Hawai’i’s watersheds

Posted on June 5, 2020 by Lissa Strohecker

University of Hawai’i professor and researcher Tom Giambelluca is looking to better understand how invasive plants, like strawberry guava on the right, disrupt the water collection function of a native rain forest like that on the left.

In Hawaiʻi, the supply of fresh plentiful water depends on the forest capturing moisture from fog drip and rain, and then move it to streams and aquifers. Scientists and resource managers know that invasive plants disrupt the capacity of a native ecosystem to collect water. In Hawaiʻi, invasive species are the greatest threat to the function of native ecosystems.

But there are many unanswered questions about how and to what degree invasive plants affect the water capture in Hawaiʻi. Water capture, depends on both rainfall and cloud or fog drip, water then moves through the forest and soil to streams and underground reservoirs (aquifers). Some water is lost through evaporation and transpiration – the movement of water from roots through the leaves and into the atmosphere.

Like straws, plants pull water out of the ground and release it into the air. Differences in both the physical structure and growth characteristics contribute to different rates of transpiration between native and invasive species. Tom Giambelluca is looking closely at those differences. Giambelluca is the director of the Water Resources Research Center and a Professor in the Department of Geography and Environment at the University of Hawaiʻi at Mānoa. He has spent much of his career looking at the impacts of invasive species on water resources in Hawaiʻi. His latest research attempts to tease out and quantify how invasive species increase the loss of water back into the atmosphere.

“One of the reasons invasive plants take over might be that they grow faster,” he says. “Faster growing plants tend to use more water” and over the long run, as invasive plants take over the native dominated forest, these differences in transpiration rates could have significant impacts on the cycle of water through the environment and the availability of water for human use.

To quantify these impacts, Giambelluca has relied on an experimental model of setting up monitoring equipment in paired sites where forest dominated by native species is growing immediately adjacent to stands of invasive plants. This site selection eliminates differences that may be caused by soil types and weather patterns in geographically separate locations. Weather can vary dramatically within small distance in Hawaiʻi. He then looks at the differences in transpiration by setting up tall towers filled with monitoring equipment and using measurements of water flow moving up the stems of sample trees.

But suitable study sites are hard to find – and funding additionally limits the number of sites he can potentially set up. With only a limited number of sites, he can’t accurately predict the impacts of invasive species may have on transpiration rates across the landscape.

So, Giambelluca is developing an experimental model wherein he can evaluate sites based on data that can be collected in a single day, therefore enabling his team to gain a better understanding of how individual differences in plant transpiration rates can impact water capture throughout Hawaiʻi. And he’s focusing primarily on leaves.

“Leaves are where the action is,” explains Giambelluca. “It’s where the plants control the uptake of carbon dioxide and release of water vapor.”

He takes a handful of measurements including the leaf area index (the surface area of all leaves over a given area), and leaf gas exchange rates of different plant species. The more leaves in an area, the higher the transpiration rates. Invasive – dominated forest tends to have a higher leaf area index (i.e,. more leaves). Plant species transpire at different rates. After he has enough data to be statistically significant, he can then combine that with distribution maps of plant species across Hawaiʻi, and better assess the impacts invasive species have on the amount of water lost through transpiration.

While still in the proposal stage with results a few years in the future, the potential outcomes from this research could help inform the decisions resource managers and funders face in setting priorities both for which species should be controlled as well as which areas are more sensitive to the impacts of invasion. In the meantime, enjoy a fresh glass of water brought to you by a native forest nearby.

For more information on Giambelluca’s research, check out his lab page at https://sites.google.com/a/hawaii.edu/ecohydrology_lab/

Originally published in the Maui News on November 9th, 2019.

Tiny golden butterfly could help halt miconia invasion

Posted on April 28, 2020 by Lissa Strohecker

Caterpillars of the golden miconia butterfly can only survive on miconia and related plants. The caterpillars get together in clumps and devour the leaves. In doing so, they may reduce the damage miconia can cause in the rainforest. — PABLO ALLEN photo

In the hills above Hāna, Nāhiku, and Keʻanae, the Maui Invasive Species Committee (MISC) crew hikes day in and day out looking for and pulling miconia plants. The team is about to grow as a kaleidoscope of golden yellow butterflies descends to assist with control.

Miconia is a notorious invader of Hawaiian forests. A single plant can produce 8 million seeds. Miconia seeds grow quickly into large plants with huge leaves that block out the sunlight preventing other plants from germinating. Miconia’s shallow roots do little to stabilize the soil. Eventually, miconia becomes the only plant in the forest; invaded sites are known for landslides and erosion that muddies streams and buries reefs.

Sam Akoi III pulls miconia from the ground in 2003. The shallow roots make the plant easy to pull but miconia does a poor job holding soil. Invaded forest slopes are prone to erosion–MISC file photo

When biologists first found this invasive plant growing in Hawaiʻi, it was a call to action. Retired state forester Bob Hobdy helped address miconia in East Maui in the early 1990s. Initially, crews focused on the area above Hāna known as “the core,” but reports started pouring in from multiple locations across East Maui. “The idea of eradication [removing every plant from the island] was set aside,” says Hobdy. “It was not feasible.” The shrubby tree was scattered from Huelo to Kipahulu, with two major infestations in Nāhiku and Hāna. Too widespread to eradicate, but too damaging to ignore, the long-term solution was biocontrol: the researched introduction of a natural enemy specific to miconia that could lessen the impact and spread of the plant.

Over the last 27 years, crews have worked to contain this invader in the field. It’s been a success: miconia never reached the West Maui mountains and it’s rare to find a plant along Hāna Highway. Meanwhile, researchers in Hawaiʻi and South America have sought out and tested insects and plant diseases in hopes of finding something that will permanently undermine the plant’s invasiveness.

In 1997, ecologists released a fungus that eats holes in miconia’s large purple leaves. In Tahiti, this fungal natural enemy opened up the canopy so that other plants could grow, but fungus didn’t have the same effect here in Hawaiʻi. The search continued.

Tracy Johnson of the U.S. Forest Service has worked to find miconia’s natural enemies for 20 years. He’s hopeful about another miconia pests, a tiny yellow butterfly that lays its eggs on the leaves. The caterpillars hatch out and to dine on the umbrella-like leaves until they become adults. “Itʻs very specific to miconia,” says Johnson. “We know from observation in Costa Rica and in Hawaiʻi that it’s one of the most damaging insects to leaves of the plant.”

Miconia’s huge leaves are major problems: they act like tarps, shading out the understory, collecting raindrops and funneling them to the ground. In comparison, native ōhiʻa and koa trees have clusters of little leaves that break up rainfall into small drops that gently water the understory. The raindrops that roll off of miconia leaves are some of the largest measured They hit the ground with extra force—and since the ground beneath miconia is bare—they contribute to increased erosion. In fact, scientists have found that erosion is greater in a miconia-invaded forest than if the rain fell on bare soil.

“Itʻs (the golden miconia butterfly) very specific to miconia,” says Johnson. “We know from observation in Costa Rica and in Hawaiʻi that it’s one of the most damaging insects to leaves of the plant.”

Though only the size of your fingernail, the golden miconia butterfly could have a big impact on invasive miconia. Native to Costa Rica, these butterflies could be a welcome addition to miconia control efforts here in Hawaiʻi. — KENJI NISHIDA photo

Enter the golden miconia butterfly, Euselasia chrysippe, —a voracious leaf eater. Johnson and colleagues from the University of Costa Rica tested E. chrysippe with 73 different plants to see what the caterpillars would feed on. In a process called no-choice testing, caterpillars are placed in a petri dish with a leaf of the plant being tested. When forced to feed on other plants, they died; only Miconia calvescens and closely related plants in the melastome family can sustain them. This is good news since Hawaiʻi has no native melastomes.

After gorging on miconia, E. chrysippe caterpillars metamorphose into butterflies and seek out another miconia plant on which to lay their eggs. Like the MISC miconia crews, they’re really good a finding the pesky plant.

The golden miconia butterfly could help halt Hawaiʻi’s miconia invasion. But there is still more to be done. Johnson is investigating other potential natural enemies, particularly an insect that eats miconia seeds. Until a suite of effective and safe natural enemies exists to control miconia, crews from MISC will continue combing the hillside in search of miconia. Any sightings of miconia can be reported to MISC at 808-573-6472.

April 2020 Update: The Hawaiʻi Department of Agriculture is soliciting comments on the draft Environmental Assessment for the release of the golden miconia butterfly. Comments are accepted through May 26, 2020. HDOA press release

This article was originally published in the Maui News on July 8th, 2018, as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

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Why can’t you keep rabbits on the ground? “Rabbit fever” affects people

Posted on April 15, 2020 by Lissa Strohecker

Laws require rabbit owners in Hawaii to keep their pets caged and off the ground. This keeps pets from escaping to start wild populations and keeps them away from ticks that could spread a potentially deadly bacterial disease: tularemia.

Several years ago, a researcher working with sparrows at a rabbit farm on Maui fell ill. He was feverish and tired, then started getting sores on his skin. Doctors weren’t sure what it was and although he was never officially diagnosed, he responded to treatment for tularemia, a disease caused by bacteria carried by rabbits, rodents, and other animals.

Officially, tularemia has never been documented in Hawaiʻi. It’s difficult to culture the bacterium and handling it poses a significant infection risk to lab workers. “If not here, there is a real threat that tularemia could, at any time, be introduced into Hawaiʻi. It affects so many animal species, and once here, mosquitoes and other blood-sucking arthropods could spread it,“ says Fern Duvall, head of Maui’s Native Ecosystem Protection and Management program with the Department of Land and Natural Resources.

On the mainland, where tularemia is widely present, the disease is rare among people. They are exposed to the disease if they handle infected animals, or if bitten by ticks or another insect that fed on an infected animal. When bacteria come in contact with the skin, they cause ulcers that spread through the body, eventually reaching the lungs. If the bacteria is inhaled, the results can be deadly.

Occasionally, there are serious localized outbreaks of the disease. The summers of 2000-2001 saw nineteen cases of tularemia on Marthaʻs Vineyard, Massachusetts– one proved fatal. The Centers for Disease Control (CDC) came to investigate. An unusually high number (14 out of 19) were pneumonic (the bacteria had entered the lungs) and many involved landscapers. What the CDC suspected was that lawnmowers or other cutting tools struck the carcasses of dead, infected rabbits, the bacteria went airborne.

In 2015, there were outbreaks in Colorado, Wyoming, South Dakota, and Nebraska. The CDC theorized these outbreaks may have been triggered by increases in rabbit populations, which grew in response to more vegetation, caused by higher than normal rainfall.

If you see a rabbit running wild, report it: 643pest.org

Vegetation, rainfall, and landscapers are plentiful in Hawaiʻi – what we don’t have are populations of rabbits running wild–at least not yet.

According to state law, people can keep rabbits but they must be contained. If kept outside, rabbits must be in a cage off the ground. The penalties for noncompliance may reflect the seriousness of the threat: loss of your pet, fines, or even jail time.

Duvall says the natural predators of rabbits in Hawaiʻi–cats, rats, or mongoose–are unlikely to keep populations of wild rabbits in check. Rabbits evolved with a multitude of predators: weasels, coyote, bobcats, owls, hawks, snakes, foxes, and raccoons. To survive high mortality rates, they breed like, well, rabbits. The female (doe) can become pregnant with her first litter at 3 months of age, and again just a month later, within days of giving birth. One pair of rabbits can produce 100 kits (baby rabbits) per season, and up to 1,000 in a lifetime.

“We know they can become invasive,” explains Duvall. In 1989, six illegally released rabbits quickly became 100 at Hosmerʻs Grove in Haleakalā National Park. On Laysan, a small island in the Northwestern Hawaiian Islands, free-roaming rabbits ate the island bare in the early 1900s, likely causing the extinction of three bird species– Laysan miller bird, Laysan ʻapapane, and Laysan rail.

Beyond environmental impacts, rabbits running wild increase the risk of tularemia. “Rabbits are more often in contact with people,” explains Duvall. Whether as pets kept outdoors or released to the wild, more rabbits mean more rabbit-human interactions. Other pets can be affected: dogs, cats, and livestock can get tularemia from ticks or direct contact with an infected animal. Early treatment with antibiotics is critical.

You can help protect Hawaiʻi. If you have a pet rabbit, spay or neuter it. If you raise rabbits, keep them contained. If you see a rabbit running wild, report it. Call the Maui Invasive Species Committee at 573-6472 or report online through 643pest.org.

This article was originally published in the Maui News June 11th, 2017, as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

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Just the act of observing can help us and our island home

Posted on April 9, 2020 by Lissa Strohecker

The Hawaiian language reflects a close tie to the land. Connecting to nature can benefit both the health of the environment and the quality of life. — BRYAN BERKOWITZ / Maui Invasive Species Committee photo.

I ka nānā no ka ‘ike.
By observing, one learns.
‘Ōlelo No’eau #1186- Mary Kawena Pukui

The Hawaiian language includes over 200 words for rain with a subset of names specific to a place. Hawaiian rain names recognize that what falls from the sky can be delicate (lilinoe, kili, uaoa); windblown (lelehuna); showery (ua nuālu); cold (kili hau or ua ‘awa); or rainbow-hued (uakoko). The reddish ulalena rain falls on Haʻikū. Uakea mists Hāna. Winds can also be place-specific: the ʻakipohe wind nips Waiheʻe; the ʻimihau wind brings storms to Lahaina.

The language of Hawaiʻi reflects the deep relationship between people and nature. The original naturalists and resource stewards of Hawaiʻi – Hawaiians–have a keen understanding of their surroundings, from the terrain and weather to local plants and animals. This understanding is also reflected in place names. Hāiʻimaile translates to the blanket of the maile vine. Kanaio recalls the shrubby naio trees that once dominated the forests of the area.

Understanding of place was essential to the survival of the first island residents. And yet today, with the distractions of modern life, it’s easy to forget that a relationship to nature is still essential: both for our well-being and the health of the environment.

Recent research on the Japanese practice of shirin-yoku or “forest bathing” has demonstrated the health benefits of intentional time in nature. Observing the natural world elevates immune response and lowers blood pressure and stress levels. Forest bathing began in Japan in the mid-1980s and is now an integral preventative health activity there. Interest has spread to the United States, with forest bathing clubs forming in urban areas. Forest bathing is not hiking, nor does it have to take place in a forest. Practitioners go out into nature to experience, with all senses, their surroundings –the range of colors, the scents and sounds in the air, the feeling of sun or breeze on their skin.

Essentially, tuning into nature as a naturalist would.

Forest and Kim Starr, early detection specialists with the University of Hawaiʻi, are self-taught botanists, entomologists, and ornithologists. They often conduct inventories of a defined area, identifying the species of plants, birds, animals, spiders, snails, and insects present.

The view from Hana’ula looking towards ʻIao Valley. Pu’u Lio is the summit between Kapilau and Kalapaokailio ridge.

“When we are out there, we’re using all our senses,” says Kim. Cued in to bird calls while simultaneously scanning for the next plant species to add to the list, the Starrs are intently focusing on their surroundings. They often return to the same place repeatedly, documenting changes. Their efforts help resource managers find invasive species before they are widespread and causing harm in the environment.

What the Starrs do – tune into the world around them and note the changes – can be done by anyone. Like forest bathing and Hawaiian practice it simply requires paying attention to our surroundings and being curious. Training is not necessary, but repetition enhances the experience, both in better understanding what belongs and does not belong in the area and achieving the health-related benefits.

Spend time outside, it’s good for your health and Hawaiʻi.

Learn more about the names of the winds and rains near your home. This list of weather names from The Ka’imi loa o ka hihi Project is a good place to start. Discover a forest bathing practice of your own—find resources and information at www.natureandforesttherapy.org. As you deepen your connection with the natural world, you can help protect Hawaiʻi from newly arrived pests; report changes in your surrounding from potentially invasive species to www.643PEST.org.

This article was originally published in the Maui News on January 13th, 2019 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

Read more Kiaʻi Moku articles.

Fountain grass threatens dryland ecosystems

Posted on April 1, 2020 by Lissa Strohecker

Jared Clapper with Hāna Lima Land Management, working on behalf of Haleakalā Ranch, was part of a team responding to an infestation of invasive fountain grass in proximity to Pu‘uokali above Kīhei. Fountain grass has a reputation for fueling a cycle of brush fires and is one of the greatest threats to the remaining dryland forest ecosystems.

On the leeward slope of Haleakalā above Kīhei rises a red dirt cinder cone named Puʻuokali. Puʻuokali means “the hill of waiting,” and is said to be one of several mo‘o (lizard deities) who were transformed into cinder cones on the summit. From her prominent vantage, Puʻuokali watches over her daughter, Puʻuoinaina on the island of Kahoʻolawe. As visible as Puʻuokali is to Maui residents, she also has her secrets. Inside the cinder cone is an intact dryland forest – a representation of the most diverse and most threatened ecosystem in Hawaiʻi. This native oasis was forgotten about until the early 1980’s when a brush fire broke out nearby and biologists rediscovered the forest.

Dr. Art Medeiros, program manager for the Auwahi Forest Restoration Project, was one of those biologists. “Puʻuokali is amazing. It’s almost the only place from Makawao to Kaupō that looks like it did when Hawaiians were the only people here.” Wiliwili, lama, naio, koaiʻa, and ʻohe are the dominant trees of this forest – these plants were essential for early Polynesians but are virtually unknown today. Dryland Hawaiian forests are the most diverse of Hawaiian forests, yet they are virtually lost: an estimated 90 to 95% of dryland forest is gone. What remains is critical: 25% of endangered Hawaiian plant species are found in these tiny refugia.

In July of 2018, Byron Stevens of the Hawaiʻi Natural Area Reserves System passed over Puʻuokali in a helicopter and saw something that didn’t belong: a two- to four-foot-tall bunchgrass with wiry leaves and purple bottle-brush flowers. Fountain grass. He sounded the alarm to multiple conservation organizations.

Fountain grass starting to invade the sacred grounds of Puʻuokali on Maui. This area is one of the few remaining places that show how Hawaiʻi looked prior to western contact.

Fountain grass is an invasive weed rarely found on Maui. Native to North Africa, it’s targeted for eradication by the Maui Invasive Species Committee. The drought-tolerant grass is able to survive in some of Hawaiʻi’s driest areas; it poses a serious threat to native dryland forest. While rare on Maui, the alien grass now covers much of the leeward coast of Hawaiʻi Island. Introduced as an ornamental in the early 1900s, fountain grass has completely transformed the Kona side of Hawaiʻi Island, turning what was once bare lava with patches of native forest into fields of grass.

“Introduced as an ornamental in the early 1900s, fountain grass has completely transformed the Kona side of Hawaiʻi Island, turning what was once bare lava with patches of native forest into fields of grass.”

Dominating arid, bare lava is one thing, but this wiry bunchgrass can also advance into intact forest, in part because it survives brushfires. Fountain grass is fire-adapted; it can regrow after flames pass over then quickly flowers and set seeds to recolonize the area. In contrast, Hawaiian forests are not adapted to fires—native plants generally donʻt survive. Fountain grass is notorious for fueling and increasing fire. At one site on Hawaiʻi Island, fountain grass (ignited by humans) has increased fire frequency from once every 500-1,000 years to once every 6-8 years.

“Fountain grass is a direct threat to the Maui County sanctuary forests such as Puʻuokali, says Medeiros. Though surrounding areas have burned, Puʻuokali has not had any wildfire, hence why so much remains. This hidden forest survived over the years partly because the surrounding landscape was so barren. There was no fuel for brushfires, and less incentive for goats and deer to cross the cinder to reach the crater. “The last refuges [of dryland forest] are in these rocky areas,” Medeiros explains. The intrusion of fountain grass changes that.

Fountain grass is almost never found on Maui, but is extremely widespread on the leeward side of Hawaii island, where it has transformed the landscape and continues to spread. Any sightings of this invasive bunchgrass should be reported — identified by its purple bottle-brush flowers that turn white as they age. MISC file photo

With that in mind, crews from multiple organizations – Auwahi Restoration Group, Haleakalā Ranch, the Maui Invasive Species Committee, and the Plant Extinction Prevention Program – came together to remove over 1,000 fountain grass plants from Puʻuokali. Completing the work will take several years. Grass seeds cover the ground and recent rains will bring a flush of seedlings. But now that the infestation has been detected, it can be managed and eradicated.

You can help. Fountain grass is often used as an ornamental landscaping plant, and people sometimes plant it on Maui by accident. Seeds can be unwittingly transported interisland on hunting or golf gear. If you see fountain grass, take a photo and report it. You can contact MISC directly at 573-MISC (6471) or the statewide pest hotline at 643-PEST, or 643PEST.org.

This article was originally published in the Maui News on September 12th, 2018, as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

Read more Kiaʻi Moku articles. Find more information about fountain grass:

Species profile: Fountain grass
Report suspected populations of fountain grass: 643PEST.org

Help protect the fragile and amazing anchialine pools of Hawaii

Posted on January 21, 2020 by Lissa Strohecker

Anchialine pools are not tide pools — they have no direct connection to the ocean. Each pool is unique, both in the salinity of the brackish water and the species that live within them. — JEFF BAGSHAW photo.

Amidst a black canvas of young lava, plant-like bacteria grow…..painting a gold border that divides the brilliant green plants from the crystalline blue waters. A diversity of shrimp, from nearly translucent to ruby red in color, float through the water while tuxedo-wearing stilts, ae’o, wander the shoreline plucking their meal from the water.

Such is the scene at a healthy anchialine pool, one of the most unique ecosystems in the world. A mix of freshwater and saltwater, these are not tide pools—anchialine pools are landlocked with no direct channel to the ocean. They are fed by seawater that seeps in underground through porous rock and mixes with surface water. The depth of the pools fluctuates, influenced by the tides, but delayed by the rocks the ocean filters through.

Anchialine pools exist in only a few places in the world and the largest concentration is in the Hawaiian Islands, where most occur on the relatively young lava fields of Big Island and Maui. Unique as they may be, these pools and the species that reside within them are vulnerable to the same threats that plague the rest of Hawaiʻi’s natural resources: invasive species, climate change, and the trampling of too many feet.

Anchialine pools can be as small as a soup pot or as large as a parking lot and no two are alike: “Each one is like a complete universe,” explains Jeff Bagshaw, Natural Area Reserve Specialist at the ʻĀhihi-Kīnaʻu Natural Area Reserve.

ʻĀhihi-Kīnaʻu has 12 groups of pools; one is the only home in the world for a tiny swimming crab. Measuring only an inch long and shy, this little creature is rarely seen. It took over 50 years before researchers could finally capture the tiny critter and identify it. Along with the swimming crab, the pools at ʻĀhihi-Kīnaʻu provide habitat for 10 species of shrimp, five of which are candidates for being listed as endangered species.

Elsewhere in Hawaiʻi, introduced trees such as kiawe and milo suck up water that would otherwise fill pools. Pickleweed, a salt-tolerant introduced plant, crowds out algal mats that feed the shrimp, which in turn feed native shorebirds. Feral goats and people wander among the pools, trampling plants and defecating along the shoreline, changing the chemistry of the pools.

Endangered waterbirds known as stilts enjoy their environment alongside an anchialine pool. Any introduction of invasive species could be extremely detrimental to this very delicate habitat. — Jeff Bradshaw photo.

The pools at ʻĀhihi-Kīnaʻu are now protected from animals by a fence around the preserve. People have been restricted from accessing the pools since 2008 but footprints are still visible in a mat of cyanobacteria, the plant-like bacteria lining the pond that adds such spectacular color. Volunteers and state crews from the Hawaii Department of Land and Natural Resources have taken on the invasive species, cutting back trees from the shoreline and lying on boogie boards to pluck out pickleweed from the native plants. This work to keep the pools and species within them healthy may help as climate change starts to affect these tiny universes.

As sea levels rise, the pools risk being swamped by the ocean. But there is hope. “If they have an undisturbed space to go to,” says Bagshaw, anchialine pools have potential to move, filling recesses in the lava field upslope as sea level rises. “So it is important to protect potential new habitat in trying to manage pools for the future.”

You can help. The ʻĀhihi-Kīnaʻu Natural Area Reserve is looking for volunteers to educate visitors about responsible behavior in the reserve. Contact Bagshaw at jeff.w.bagshaw@hawaii.gov

This article was originally published in the Maui News on August 13th, 2017, as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

Read more Kiaʻi Moku articles.

Perils of pampas on West Maui Mountains

Posted on November 18, 2019 by Lissa Strohecker

Steve Perlman examining invasive pampas grass in Kauaʻula Valley. — MISC file photo

With plumes that bring to mind ostrich feathers, pampas grass first became popular in the Victorian era. Fluffy seed heads decorated the most fashionable hats, homes, even carriages. Interest surged again in the mid-1960s and the plant became a fixture in some yards and golf courses on Maui.

Today, pampas is taking over Instagram feeds: the plumes are used to add a Bohemian/Southwestern flavor to wedding bouquets, centerpieces, and home décor. But here on Maui, this ornamental grass is associated with a different trend: loss of habitat for threatened and endangered species and destruction of the watershed.

“But here on Maui, this ornamental grass is associated with a different trend: loss of habitat for threatened and endangered species and destruction of the watershed.”

Pampas can grow on nearly vertical slopes, displacing native plants that support populations of threatened and endangered animals and disrupting watershed function. With seeds that can travel 20 miles in the wind, ornamental plantings can infest far away forests. — MISC file photo

Pampas is a clumping bunchgrass native to South America. The leaves are razor-sharp, dying back each year but leaving dry foliage that accumulates and can fuel wildfires. The decorative plume is the seed-head and a single plant can spread millions of tiny seeds on the wind – in some cases, as far as 20 miles. Seeds germinate readily on bare soil, but with enough moisture, the invader finds footholds in patches of moss or tree bark. The plant competes with native vegetation and could replace habitat and food resources used by native birds and in doing so disrupting the layered structure of the rainforest so important for aquifer recharge.

This grass knows no limits – it has been found growing from sea-level to the rim of Haleakalā Crater at 9000 feet. Water, or lack thereof, doesn’t seem to be a key determinant for where pampas lives. It will (and does) grow in the wettest rainforests and on the driest hillsides, often emerging in rain-drenched bogs and wind-scoured cinder slopes.

Pampas grass has been a target for eradication on Maui since the mid-1990s when staff from Haleakalā National Park started finding feathery plumes in the crater. MISC has been working to stop pampas since the inception of the program. Through continued control efforts, the East Maui population has been in steady decline but without consistent support and control efforts, progress could stall.

MISC employee scoping out pampas. Invasive plants don’t always grow in easily accessible areas. The slopes of West Maui are so steep that efforts to remove plants like pampas grass necessitate the use of helicopters. — MISC file photo

The West Maui pampas population has always presented challenges. Much of the difficulty lies in the rugged terrain and weather, limiting access for much of the year. On East Maui, crews can access much of the known pampas infestation by timing helicopter flights early in the day and camping and hiking to access plants from the ground, but the slopes of the West Maui Mountains are more vertical than anywhere else in Maui, affording few camping sites and making ground access difficult or impossible. Pampas, on the other hand, thrives on the bare soil of the erosion-prone slopes. When that happens, our crews depend on helicopters to seek out and remove the invader.

Thanks to funding from the National Fish and Wildlife Foundation, MISC crews have been scouring the cliff faces of West Maui over the last year. They are looking for pampas plumes and the tell-tale growth pattern of the plant before it goes into flower. If they find the plant, they record the location by on a GPS and then return by helicopter but this time loaded down with an external tank and 80’ long line and weighted sprayer attached. This allows the pilot and crew to hold hover over the plant and remotely trigger a tiny spray of herbicide directly to the grass below.

Despite nearly constant rescheduling of flights due to weather or a need for the helicopters to go fight a brush fire, crews have flown over 15,000 acres on West Maui from 2017 to the summer of 2019. This coverage has led to the detection and removal of nearly 1,900 pampas plants from the mountain slopes– a huge leap forward in the effort to stop this invader from taking over prime habitat for native birds, plants, and invertebrates.

You can help. First, become familiar with what pampas grass looks like (mauiinvasive.org/pampas/). Second, never plant pampas grass or import it for décor or floral arrangements. The Division of Forestry and Wildlife has designated pampas as one of Hawaiʻis most invasive horticultural plants. Finally, report any pampas grass you find. You can report it to MISC: 573-6472, miscpr@hawaii.edu, or online at 643PEST.org

This article was originally published in the Maui News on September 14th, 2019 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

Read more Kiaʻi Moku articles.

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