Maui Invasive Species Committee (MISC)

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Sap-sucking insect threatens native naio trees

Posted on September 26, 2019 by Lissa Strohecker

While it may look healthy at first glance, this young naio plant is under attack from a tiny invasive sap-sucking insect known as the naio thrip. Initial symptoms are a crumpling effect on newly sprouted leaves. The pest is currently known only from O’ahu and Hawaiʻi Island — OISC file photo.

From Maui’s coastlines to our mountain slopes, the naio tree provides shelter for native animals and helps prevent erosion. Naio is a shape-shifter: it can be a crawling prostrate shrub or an 80-foot tall towering tree. Itʻs versatile and adaptable. Along the shore, naio plants easily withstand the constant salt spray. At the top of Haleakalā, these indigenous plants endure bracing cold and wind. But the hardy naio trees of Hawaiʻi are at risk from a minuscule, sap-sucking insect, the naio thrip.

At 1/20th of an inch, about the size of the comma in this sentence, the naio thrip is so tiny it is easily overlooked, but can wreak havoc on naio trees. Within four hours of a thrip beginning to feed on a naio plant, the munched leaf will start to curl. After months of feeding, the plant becomes misshapen and crumpled. Eventually, the thrips will kill naio trees. Young plants are particularly vulnerable.

A young naio plant shows early symptoms of naio thrip infestation – curling and discoloration to the new leaves. — OISC file photo.

The minute thrips were initially found on Hawaiʻi Island in 2008. Infestations there werenʻt found soon enough and many stands of naio have since perished. Resource managers knew it was only a matter of time before the pest spread. To reduce the risk to naio elsewhere, the Hawaiʻi Department of Agriculture implemented a quarantine on naio, prohibiting the movement of the plant from Hawaiʻi Island. Resource managers statewide collaborated on early detection and rapid-response plans specific to each island, recognizing the likelihood that these insect pests could spread throughout the island chain.

So in November 2018, when a native-plant enthusiast on Oʻahu saw strange galls and crumpling on new growth of a naio, and posted a photo online, the response team was prepared for action. Rachel Neville, manager of the Oʻahu Invasive Species Committee (OISC), reports that the survey team had inspected 619 naio plants within a month of the post.

A size comparison of the naio thrip to a thumb. An early detection and rapid response plan in place on Oahu has guided containment efforts after the pest arrived there in November of 2018. — Oahu Invasive Species Committee photo.

“Having a rapid response plan for this detection was so helpful. We had a list of naio that should be checked island-wide and all the agencies and landowners came together to help delimit. We were able to determine the extent of the infestation in one week, which meant treatment got underway very quickly,” says Neville. During island-wide surveys, the response team (including staff from a half-dozen resource management programs) found only 42 infested plants, all of which were in urban settings, isolated from natural areas and wild populations. All infected plants have been treated and the survey team is continuing to check naio for signs of thrips. Citizen scientists are helping by submitting photos through the OISC Adopt-a-Naio program.

Naio thrips have yet to be found on the Valley Isle. The Maui County Early Detection and Rapid Response plan, developed by eight resource-management and protection organizations, calls for monitoring over 30 naio populations across Maui, all of which were thrips-free as of February 2019. The surveys are repeated every six months.

You can help. If you have naio in your yard, or know where there are some, check them regularly for signs of thrips: crumpling and curling leaves.  Find out more about naio thrips and the Maui County Early Detection and Rapid Response Plan online at https://dlnr.hawaii.gov/hisc/info/invasive-species-profiles/naio-thrips/

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 March 10th, 2019 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

Read more Kiaʻi Moku articles.

Filed Under: Kia'i Moku Column Tagged With: 2019, leaf curlling naio, naio pests, naio thirp

Press release 9/23/19: New infestation of little fire ants found in Waihee Valley

Posted on September 23, 2019 by Lissa Strohecker

Little Fire Ants on a hibiscus flower in Waihee Valley. MISC file photo

In late August 2019, a Waihee Valley resident called the Maui Invasive Species Committee (MISC) to report stinging ants. She feared they were little fire ants (LFA) after being stung on her neck and under her collar while working near fruit trees. Staff from MISC contacted the resident and arranged a site visit to investigate the report. The ants were identified under a microscope as little fire ants or Wasmannia auropunctata.

The next day, a team from the Hawaii Department of Agriculture (HDOA) and MISC conducted surveys in the area, which is adjacent to the Waihee River. Initial surveys indicate that LFA are present on three properties. The infestation is estimated to cover four to five acres, mostly in overgrown vegetation and away from homes. Little fire ants were detected next to the river, raising concerns that the ants may have moved downstream; however, preliminary riverside surveys below the infestation zone did not detect any LFA.

Area residents who have encountered stinging ants—particularly those who have been stung on their neck and upper body after working with or under vegetation – are urged to report suspect ants by contacting either the Maui Invasive Species Committee at 573-MISC (6472), the Hawaii Department of Agriculture on Maui at 873-3080, or online at 643PEST.org.

LFA on a coconut. Multiple colonies can live within a coconut and simply the act of moving a coconut, mulch, or anything stored outside can spread an infestation to a new area. MISC file photo

This infestation is the fourteenth detection of little fire ants on the Valley Isle since 2009 and the second detection of LFA on Maui this year, following the April detection in the Happy Valley neighborhood of Wailuku. MISC is actively treating five sites; the Waihee Valley site will be the sixth. After undergoing a rigorous treatment regimen, little fire ants are thought to be eliminated from other sites, though MISC continues to survey to ensure they are gone. 

The source of the infestation is unknown at this time and there is no known connection between this one and a previously-infested site at a farm in Waihee. Based on the size of the new infestation, experts estimate little fire ants have been present for five or more years.  

The little fire ant has been called one of the 100 worst invasive species globally (IUCN Invasive Species Specialist Group). They were first detected on Hawaii Island in 1999 and Maui in 2009. Little fire ants reach incredible densities (80 million ants per acre) and outcompete many other insects and small vertebrates. LFA live in trees as well as on the ground. People often discover the ants by brushing against heavily-infested bushes or in windy conditions when the ants fall off plants or trees. Unsuspecting victims of the “ant rain” are left with painful stings and animals can be blinded. On Hawai‘i Island, little fire ants are now widespread. People describe being at their “wit’s end” and unable to take their keiki to the places they learned to fish, hunt, surf, and hike. Left unchecked, this species will affect Maui’s environment, and agriculture, and forever change our quality of life.

There will be a community meeting on Wednesday, October 9th at 6 pm at the Waihee Elementary School. Officials from MISC and HDOA will share information on the threat of little fire ants, the current status of Maui’s infestations, the plan for treatment, and community efforts to prevent the spread. Learn more about LFA, including how to collect samples, at www.stoptheant.org

Contact:               Lissa Strohecker, Public Relations and Education Specialist                                Brooke Mahnken, LFA Coordinator
                               Adam Radford, MISC Manager 
                               Maui Invasive Species Committee
                               PH:  (808) 573-6472

                                Email: miscpr@hawaii.edu

  • Little fire ants on the stem of a hibiscus flower. MISC file photo.
  • LFA are attracted to peanut butter. Baiting a chopstick with peanut butter and returning after 45 minutes to pick it up is one way to sample your yard for little fire ants and other species. Find instructions at http://stoptheant.org/report-little-fire-ants/ MISC file photo.

Filed Under: Little Fire Ants Tagged With: little fire ants, press release, Waihee Valley LFA

Invasive longhorned beetle bores into fruit trees, threatening crops

Posted on August 28, 2019 by Lissa Strohecker

Large beetles have begun to spread across Puna but have not yet been detected on other islands. They pose a threat to fruit growers on the island and throughout Hawaii. Native to Queensland, the Acalolepta aesthetica, longhorned beetles are dimpled and fuzzy on their abdomens. — Photo courtesy of Big Island Invasive Species Committee.

In 2009, a resident of Orchidland subdivision in Puna on Hawaiʻi Island found a strange beetle with extremely long antennae on the screen door. This report marked the first detection of a new species of longhorned beetle, Acalolepta aesthetica, in Hawaiʻi and the United States. Lacking an official common name, the beetle is called the Queensland longhorn beetle, reflecting its native home in Australia.

Despite survey efforts by the Hawaiʻi Department of Agriculture, the beetle wasn’t detected again for years, but that first incursion wasn’t a one-off and its population continued to grow. Four years later it was seen again. Sightings increased as the beetles spread across Puna. Over the last 3 months, the Big Island Invasive Species Committee has received over a dozen reports.  

The arrival of this new insect has officials with the Hawaiʻi Department of Agriculture (HDOA) concerned. According to HDOA entomologist Darcy Oishi, the Queensland longhorned beetle could significantly damage citrus and other trees.  The larvae tunnel through living wood creating big galleries, similar to termites, but on a much bigger scale. Oishi says, “They make these giant weeping wounds in branches or the trunk of a tree. The damage can cause dieback in a limb or the death of a tree.”

“They make these giant weeping wounds in branches or the trunk of a tree. The damage can cause dieback in a limb or the death of a tree,” says Oishi.

Not much known about this beetle, perhaps because it’s not a pest elsewhere. Its arrival in Hawaiʻi marks the first time this beetle has acted invasively with potential impacts only now being realized. The list of trees damaged by beetle larvae continues to grow. It’s been found tunneling through lemons, limes and other citrus; Polynesian-introduced trees such as ulu (breadfruit) and kukui; favorite food crops like cacao (chocolate) and possibly avocado; and introduced species such as gunpowder trees and sago palm. As the current world expert on the beetle, the Hawaiʻi Department of Agriculture has not identified any natural enemies in Hawaiʻi nor any effective controls methods.

Complicating research on control options is the presence of native longhorned beetles in our state. Important both as wood decomposers and food for native birds, our Cerambycid beetles are one of the many native insects that show amazing rates of adaptive radiation. From what entomologist estimate was three distinct arrivals, over 120 species evolved. One of the largest native insects in Hawaiʻi is a Cerambycid beetle; measuring 2 inches from ­tip to tail with sweeping antennae as long as its body, Megopis reflexa is closest in appearance to the invasive Acalolepta aesthetica.

The new wood-boring pest is not yet known from Maui or any of the other Hawaiian Islands, but farmers and residents can take steps to prevent its arrival. The best way to keep it from moving interisland is to not bring green woody material between islands, particularly if the vegetation shows signs of damage, such as weeping wounds where a beetle may have laid its eggs and larvae entered the tree.

The larvae of Acalolepta aesthetica, a longhorned beetle from Australia, leaves large weeping holes in tree trunks of food crops like citrus and cacao. — Photo courtesy of Hawaii Department of Agriculture.

Be alert to sightings of the beetle, often attracted to house lights at night. The adult measures from 2-4.5cm (3/4-1 ¾ inches) in length. The antennae on the male are twice as long as the body – giving rise the moniker “longhorned.”  Antennae on the female are shorter. On either side of the thorax (the body part behind the head) are two thorn-like spines. The abdomen is dimpled and looks as though covered in peach fuzz. In contrast, the native Megopis beetle has ridges running down the abdomen, giving it a striped appearance.

There is a native longhorned beetle – Megopis reflexa – that is nearly the same size as the invasive Queensland longhorned beetle. Look for stripes running the length of the body. –Photo courtesy of Ross Kamimoto

Oishi also suggests looking for wounding on trees.  The beetle larvae can be even larger than the adults and as they leave the tree to mature, they leave behind large holes, up to 1.25 cm (1/2 inch) in diameter, as big around as a pinky.  Other indications are sawdust-like frass being pushed out of holes on the trunk, girdling on trunk, sap oozing from where the adult laid eggs, and branch dieback and drop. Find more details and the official pest advisory on the HDOA website: http://hdoa.hawaii.gov/pi/ppc/new-pest-advisories/.

On Maui, report any suspected sightings. Collect the beetle and contain it in a secure container. Take clear digital photos of the beetle and record the location, type of plant or tree, date, and how you found it. If you see damage on a tree, take photos. Use an object (coin or ruler) for reference.  Email the photos and the information to HDOA.PPC@HAWAII.GOV or report it online through 643PEST.org.

 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 on August 10th, 2018 as part of the Kiaʻi Moku Column for the Maui News.

Read more Kiaʻi Moku articles.

Filed Under: Kia'i Moku Column Tagged With: 2019, Queensland longhorn beetle

Illegal dumping risks spreading invasive species

Posted on September 11, 2018 by Lissa Strohecker

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. Photo by Maui Invasive Species Committee.

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.

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 Hawaii 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, illegally-dumped rubbish has been the vector for at least five introductions of coqui that MISC is aware of.

 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 safe guards.  Photo by Maui Invasive Species Committee.

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.

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 (CRB) lay eggs in mulch and so stopping the movement of infested debris is a priority for the CRB teams on O’ahu. Photo by U.S. Army Garrison Hawai’i. 

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 their 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 Hawaii 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 on May 13th, 2018 as part of the Kia’i Moku Column for the Maui News.

Filed Under: Decontamination, Invasive Animals, Kia'i Moku Column Tagged With: 2018, coqui frogs, illegal dumping, little fire ants, Spread of coqui

Introduced songbirds can be invasive in Hawai’i

Posted on August 15, 2018 by Lissa Strohecker

There are other birds not known to be on Maui that should be reported immediately if seen. The red-vented bulbul is one such species; — K. HARI KRISHNAN photo

In March of 2018, a cluster of reports from Maui residents and visitors of White-rumped shamas in West Maui came in on the online birding database, eBird. The Maui Invasive Species Committee and other organizations had received reports before, but the frequency of reports caught the attention of Chris Warren, who works with the Maui Forest Bird Recovery Project. These birds weren’t known to be widespread on Maui.  White-rumped shamas are not native to Hawaiʻi. These introduced species have established breeding populations on Oʻahu, Molokaʻi, Lānaʻi, and Kauaʻi, but only scattered sightings had been reported on Maui in the past. No new invasive species is a welcome addition to our fragile ecosystems here on Maui. Warren and his team went to Kapalua and the Honolua area to investigate.

“Pretty soon it was evident that there were more than just a few birds out there,” says Warren. This wasn’t a case of a lone bird—the team found shamas in streambeds and forested areas from Napili to Honolua Bay, but the full extent of their population is still unknown.

White-rumped shamas are native to western Indonesia, southern India and southwestern China but have been introduced elsewhere as a result of their popularity as cage-birds and songsters. Here, their diet consists mainly of small insects that they pounce on while in the underbrush. According to Warren, there are other introduced birds that may pose a greater threat to native birds than the shama but what has resource managers concerned is that a bird new to the island went unreported for so long. “Our native birds are already at a tipping point, the last thing they need is another competitor,” he says.

White-rumped shamas are part of the host of bird species brought to Hawaiʻi during an era of bringing in song-birds. By the turn of the 20th century, avian malaria and introduced predators had already brought native Hawaiian bird populations to low levels. Residential gardens were quiet but for the squawking of mynas and calling of doves. The socialites of Honolulu formed garden clubs for the purpose of importing song-birds—which only put added pressure on native ecosystems. From the 1920s up until the 1960s, when the practice was restricted, these garden clubs introduced many species of songbirds. Not all of these birds became established, but many did, and the musical White-rumped shama was among them.

Shamas were first released in Kauaʻi in 1931 and then in Oʻahu between 1938 and 1940. Those 89 birds then spread, reaching Molokaʻi in 1997 and Lānaʻi by 2009. They may have crossed between the islands on their own, but it’s also possible that humans helped them spread inter-island.

Warren and his colleagues are not exactly sure how far the shamas have spread on Maui. With the help of other resource management organizations, Maui Forest Bird Recovery Project is working to determine the distribution of these singing flycatchers. You can help!

  • White-rumped shamas are 9-11 inches long, about the size of a northern cardinal.
  • They have long tail feathers and spend much of their time in the underbrush.
  • Males have a glossy bluish-black back and head, a chestnut brown belly, and white patch feathers under their tail. Females have a tan head and back with chestnut belly.
  • Their song is impressive, both in range and volume, making them hard to miss.
  • Find information with photos and recordings, online: The Cornell Lab of Ornithology – White-rumped Shama. Report sightings, with a photo or recording through the online pest reporting system, 643PEST.org.
The red-vented bulbul is not known from Maui and should be reported immediately if seen. This bird resembles a cardinal but the head is completely black and it has a distinctive red patch on the underside. Bulbuls are serious agricultural pests on other islands. Report any sightings to 643PEST.org. — K. HARI KRISHNAN photo

While the white-rumped shama is likely here to stay, however, there are exotic bird species present on other islands that have not yet reached Maui. Red-vented bulbuls found on Oʻahu are one example: they are voracious fruit eaters and serious agricultural pests that quickly dominate the landscape.

To keep a new invasive species from becoming established, finding it early is essential. If you see something new in your yard, birds notwithstanding, take a few minutes to report it on the statewide pest reporting system. Either call 643-PEST(7378) or use the online report form, 643PEST.org.

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 on May 13th, 2018 as part of the Kia’i Moku Column for the Maui News.

Filed Under: Invasive Animals, Kia'i Moku Column, Report a Pest Tagged With: 2018, Birds in Hawaii, Kia'i Moku

Natural enemies could tame invasive Himalayan ginger

Posted on June 5, 2018 by Lissa Strohecker

Though not invasive in India where it is native, Himalayan ginger can completely transform a Hawaiian rainforest like it has in this section at 4,000-foot elevation above Haiku. Inset: Ginger fruits are spread long distance by birds and rats. FOREST and KIM STARR photo

The subtropical rainforests in the foothills of the Himalayan Mountains are amazingly diverse. In sections of India and Nepal, the forests are similar to Hawaiian rainforests in both temperature and rainfall-but the flora and fauna are radically different: this is the land of elephants and red pandas; 600 species of butterflies live here and over 400 species of orchids. But amongst the exotic plants there is one

The fruit of Himalayan ginger is a tasty treat for non-native birds, but this means the seeds are spread throughout the forest. Photo courtesy of Forest and Kim Starr.

that might be familiar to residents of Hawai’i-a yellow-flowered ginger that covers vast sections of Hawaiian rainforests.

Himalayan ginger, Hedychium gardnerianum, is native to the Himalayan foothills. There, it evolved over millennia supporting a diversity of species: the sweet nectar is a food for the long-tongued butterflies of the region and the plant lives in harmony with the species that surround it. Yellow flower stalks dot the landscape amongst hundreds of other orchids, gingers, ferns, and trees.

But in Hawai’i, Himalayan ginger dominates the landscape-growing fast and paving its way into the forest in an unrelenting march.

“Himalayan ginger displaces critical native vegetation layers, limits canopy tree recruitment, and hogs water resources in their massive rhizomes (roots). As it takes over and forms monotypic stands, it negatively impacts native flora and fauna, including Hawai’i’s unique arthropod complex and the Hawaiian honeycreepers,” says Alison Cohan, director of the Maui Nui Forest Program with The Nature Conservancy (TNC).

Introduced as an ornamental, Himalayan ginger escaped backyards and began invading rainforests of East Maui in the mid 1950’s. With seeds dispersed far and wide by birds and rats, the weedy plant spreads by leaps and bounds into the forest. Today, much of the mid-elevation rainforest of East Maui is a patchwork of native forest and alien ginger. But there is a lot left to protect: many ginger-free areas remain, including most of West Maui.

Ginger is a formidable foe and removing the plant is no simple task. Roots pave the forest floor like asphalt and every part of the rhizome must be removed. Bagged rhizomes take years to decay and if there is the slightest hole in the bag, hardy shoots emerge. If using herbicide, every portion of the root has to be treated. Plants on steep slopes and cliffs are inaccessible and impossible to remove until the weight of the water-logged roots causes entire sections to collapse in a landslide.

Why would ginger be a pest in one place but not another?

Djami Djeddour, weed biocontrol scientist with the Centre for Agriculture and Bioscience International, inspects a lone Himalayan ginger plant in India while searching for insects and fungi that live on the plant where it is native. These insects may be responsible for keeping the plant in check. DJAMI DJEDDOUR photo

The answer to that question is on the minds of resource managers in Hawai’i as well as New Zealand, Australia, and South Africa where the plant is invasive. With funding from organizations like TNC and the Hawai’i Invasive Species Council, research scientists traveled to India and collected insects and fungi that live on Himalayan ginger hoping to discover what keeps the fast-growing herb in balance there. An effective natural enemy could be a game changer for Hawai’i.

An effective natural enemy wouldn’t eliminate the plant, just bring it into harmony with the surrounding environment, much like it is in India and Nepal.

One of the most promising insects is a Cloropid fly that lives only on Himalayan ginger. The larvae live inside the stem stunting the growth and reducing flower production. Ginger natural enemies may be ready for release in New Zealand soon, promising progress for Hawai’i.

“The Nature Conservancy had been doing ginger work in Waikamoi for over 30 years, systematically conducting ginger control—containing the core population at the western edge of Waikamoi and eradicating outliers in native forest,” explains Cohan. Crews with Haleakala National Park work on the flowering pest in Kīpahulu Valley but the plant is widespread and thrives unchecked in wet places throughout the state.

There are ways you can help. Consider what you call the plant: though known for years as kāhili ginger, a pest destroying the rainforest does not deserve a moniker reminiscent of Hawaiian royalty much less one that might suggest that it belongs here. Perhaps call it toilet-brush ginger, as suggested by Pat Bily of TNC after years of removing it. Do not plant Himalayan ginger in your yard and remove it from your property before it spreads. Finally, participate in The Nature Conservancy’s quarterly volunteer trips removing ginger from Waikamoi Preserve. Contact hike_waikamoi@tnc.org if interested.

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 April 8th, 2018 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

Filed Under: Solutions, Watershed impacts Tagged With: 2018, biocontrol, Himalayan ginger, kahili ginger

Native species recovering at Mokio Preserve on Moloka’i

Posted on May 25, 2018 by Lissa Strohecker

Jay Penniman of the Maui Nui Seabird Recovery Project sets up an acoustic monitor near the Laysan albatross decoys at the Mokio Preserve on Molokai. The speaker in the foreground broadcasts mating calls for the very rare Laysan albatross during the day, while acoustic monitors record nighttime activity from other seabird species like the wedge-tailed shearwater. — BUTCH HAASE / Molokai Land Trust photo.

On the windswept, northwestern corner of Moloka’i there is an old cattle pasture that, until recently, was covered in kiawe, buffelgrass, and lantana. But underneath the invasive plants, seeds of native species lay waiting, ready to grow if given the chance. Endangered Hawaiian insects found refuge in pockets of the sea cliffs. Seabirds patrolled the coastlines. Their wait may be over.

In 2008 the Molokaʻi Land Trust began to manage Mokio, five miles of coastline between the state-owned Ilio Point and The Nature Conservancy’s Moʻomomi Preserve. This former pastureland was never developed and is rich in both cultural and biological resources. Seasonal wetlands support the largest population of an endangered fern, ʻihiʻihilauākea, or four-leaf clover fern, in the State. Adze quarries and pre-contact Hawaiian housing sites remain relatively intact. It is a promising seabird nesting habitat, already in use by the koaʻe ʻula and koaʻe kea (red-tailed and white-tailed tropicbirds) that nest in the cliff faces and noio (black noddy) that raise their young in caves. But years of cattle and deer traffic have taken a toll on the native plant community.

The first step in restoring the area: fencing out large grazing animals. “Sixty acres are fenced,” says Butch Haase, executive director of the Molokai Land Trust. “We’ve converted a kiawe, lantana, and buffelgrass-dominated landscape into a native-dominated landscape.”  Seeds of native coastal plants have begun to sprout after decades of dormancy. Volunteers planted seedlings farther inland where the seed bank was depleted by years of cattle grazing. Their efforts are proving successful: carpets of yellow-flowered nehe, ʻilima, and a rare orange ʻōhai now thrive where kiawe and other invasives once grew.

“Their efforts are proving successful: carpets of yellow-flowered nehe, ʻilima, and a rare orange ʻōhai now thrive where kiawe and other invasives once grew.”

Native habitat attracts native critters. These native coastal plants feed and house critically endangered Hawaiian yellow-faced bees. The low-growing vegetation is the perfect place for seabirds to forage. And they do – the variety of seabirds seen at Mokio rivals that of another birding hotspot in the Hawaiian Islands – Kilauea Point on Kauaʻi. Uau Kane (wedge-tailed shearwater), a (both red-footed and brown boobies), and Kaupu (black-footed albatross) are nesting here. Moli – the Laysan albatross – has been sighted along the northern coast of Molokai, landing at Ilio, Anapuka, and Kalaupapa. This led Haase and his crew to wonder if perhaps albatross belonged at Mokio, too.

Orange-flowered ohai (foreground) is one of the endangered plants that have begun to germinate now that invasive species have been removed from the Molokai Land Trust’s Mokio Preserve. Ohai, yellow-flowered ʻilima papa, and other native coastal plants create a low-growing carpet the feeds and houses endangered yellow-faced bees and creates habitat for native seabirds. — BUTCH HAASE / Molokai Land Trust photo

With rising sea levels threatening primary albatross nesting grounds in the Northwest Hawaiian Islands, scientists are trying to increase nesting sites in the main Hawaiian Islands. So Haase, working with the American Bird Conservancy, Maui Nui Seabird Recovery Project, the US Fish and Wildlife Coastal Program, and the Department of Land and Natural Resources, deployed a fourteen albatross decoys complete with pre-recorded albatross calls. Within ten days an albatross had landed, scraping around to investigate a potential nesting site.

This albatross was alone, checking out new territory as young albatross often do, but the amazingly quick response rate is promising. Haase and the rest of the project team hope that within two years albatross could be nesting at Mokio.

That solidifies a deadline for another project at Mokio: the construction of a predator-proof fence to protect ground-nesting seabirds from feral cats, dogs, mongoose, rats, and mice. These predators attack adults and eat their eggs or hatchlings. (Presently, labor-intensive trapping keeps the predator population down). When the fence is complete it will protect 85 acres of potential nesting habitat for Hawaiian seabirds as well as migratory seabirds like kōlea and the kioea, bristle-thighed curlew, a shorebird that cannot fly during its winter molt in Hawaii.

A restored native coastal region in Molokai has been very reassuring to local inhabitants and environmentalists alike. — MISC file photo

The changes at Mokio are dramatic – a cattle pasture transformed into a growing seabird colony now full of native plants. The success so far highlights the resilience of Hawaiian species and their ability to recover when invasive plants and animals are removed. Work at Mokio is ongoing and you can help: Molokai Land Trust welcomes volunteers, both residents of Molokai and visitors from off-island.  If you would like to help in recovery efforts, send an email to volunteersmlt@gmail.com. Follow the progress of the project at molokailandtrust.org and look for them on Facebook.

This article was originally published in the Maui News on May 13th, 2018, as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

Read more Kiaʻi Moku articles.

Filed Under: Kia'i Moku Column Tagged With: 2018, coastal restoration, Mokio Preserve, Molokai Land Trust, yellow-faced bees

The native dragonflies and damselflies of Hawaiʻi

Posted on May 18, 2018 by Lissa Strohecker

Megalagrion pacificum is an endangered damselfly found on Maui. Evolving over 20 million years of isolation, these native damselflies and dragonflies are threatened by habitat loss and introduced predators like mosquito fish. — U.S. Fish and Wildlife Service / DAN POLHEMUS photo

Twenty million years ago the Hawaiian Island chain was very different from what we see today. Laysan and Gardner Pinnacles were the prominent islands in the archipelago and the main Hawaiian Islands were merely raw lava flowing through the interior of the planet. Around this time a damselfly arrived to the chain, beating the odds in a successful journey across half an ocean.

This single event led to the evolution of some 26 species and sub-species of native damselflies in Hawaiʻi that exist today, according Dr. Dan Polhemus, the Aquatic Ecosystem Conservation Program Manager for the Pacific Islands Fish & Wildlife Office within the U.S. Fish and Wildlife Service. He has studied dragonflies and damselflies throughout the Pacific as well as here on Maui.

Perhaps our most spectacular native insects, damselflies and dragonflies were once widespread throughout the islands. Known as pinao in Hawaiian, these insects now exist only in a tiny portion of their historic range. Introduced predators and habitat loss are to blame. Several species are so rare that they are listed as threatened or endangered. They are often extremely localized; some species are now only found in a single stream.

Pinao adapted to take advantage of the resources available in Hawaiian ecosystems.  They live in a remarkable range of habitats, from mountain streams to marshlands and brackish anchialine pools.

Perhaps because streamflow is often intermittent, some species adapted to survive outside of streams and pools. There are naiads (larval stage of development) that take advantage of water seeps and pockets of rain that collect in the leaves of ʻieʻie vines. One species of damselfly is completely terrestrial – an adaptation existing in only a few other damselfly species in the world.  Their young live in the moist understory of uluhe fern and lack gills found during other damselfly species’ naiad stages.

These hunters evolved eating small insects, both in the water and as they fly through the air. Today, pinao eat a variety of prey, including introduced insects such as mosquitoes. “They are essentially mid-air fighter planes,” says Polhemus. They hunt by folding their legs into a basket to snatch insects from the air. But these aerial predators are prey nowadays.

Lowland marsh and riparian areas have been converted and streams have been diverted. “Intermittent pools have a lot of invasive species,” says Polhemus. Without regular flow to flush out the introduced aquatic species, these pests, such as mosquito fish become established. While the handful of introduced dragonflies have fish avoidance behaviors, the native species, having spent the last 20 million years without predators, are easy prey for non-native fish and other insectivorous invaders. Like native birds in the face of tree-dwelling predators like rats, the larvae are easy picking for voracious mosquito fish. “Where mosquito fish are present, you don’t find native damselflies’” says Polhemus.

Bullfrogs and bulbuls (an invasive bird not present on Maui but found elsewhere in Hawaiʻi) also pose a threat to these ancient colonizers. Bullfrog tadpoles eat dragonfly naiads and bulbuls have been seen snatching the insects from the air.

Ants are another predator. The young naiads climb out of the water to morph into adults on land. Their skin splits open and wings unfold. As they wait for their skeleton to harden and wings to dry they are vulnerable to invasive ants.

There are several species of introduced dragonflies, and most of the dragonflies at low elevation are finddamselflies (distinguished from dragonflies by their ability to fold their wings back at rest) are now found mostly in upper elevations on the Hawaiian Islands, with two species found only on Maui. The largest dragonfly in the United States is found only in Hawaiʻi. Anax strenuus, the Hawaiian giant dragonfly has a wingspan of 6 inches.

You can help protect these unique animals: If you can no longer care for your fish or other aquatic friends, re-home them with someone who can. Never release them into the wild as they can cause ecological damage by pushing out native species, which play an integral role in a healthy Hawaiian ecosystem. Support legislation to maintain streamflow and prevent pollution. To learn more about these fascinating creatures visit: https://dlnr.hawaii.gov/wildlife/files/2013/09/Fact-Sheet-Odonata-damselflies-dragonflies.pdf

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 February 11th, 2018 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

Read more Kiaʻi Moku articles


If you are interested in learning more about the native insects found in Hawai’i, you may enjoy:

  • Mapping the Kamehameha Butterfly with Your Help
  • Look closely–the endemic insects of Haleakalā

Filed Under: Kia'i Moku Column Tagged With: 2018, damselflies, dragonflies, endemic Hawaiian insects, odonata, pinao

Celebrate invasive species prevention: nominate a Maui County landscaper for the Malama i ka Aina award

Posted on May 10, 2018 by Lissa Strohecker

2017 Award Ceremony: Allison Wright of the Maui Association of Landscape Professionals, Teya Penniman of the Maui Invasive Species Committee, Joe Imhoff, Henry Imhoff, Sara Tekula, and Jeremiah Savage of the County of Maui. Photo by Bryan Berkowitz/Maui Invasive Species Committee.

 

Nominations are now being accepted to honor invasive species prevention efforts within Maui County.  The Malama i ka Aina Award is presented annually to a landscaper, plant provider (retail and wholesale nurseries and garden shops), or commercial/agricultural property owner/manager to recognize their efforts to keep invasive species out of Maui County.

The award is a cooperative effort of the Maui Association of Landscape Professionals, the Maui Invasive Species Committee, and the County of Maui.

The winner will be announced Saturday, June 16th at the Maui Association of Landscape Professionals’ Maui Garden and Landscape Expo at the Maui Mall.  The winner will receive a plaque, a glass sculpture by artist Jupiter Nielsen, a one-year free membership with the Maui Association of Landscape Professionals and local media recognition.

Applicants are requested to explain how the nominee’s activities or decisions have con

The awardee will receive a glass sculpture by local artist Jupiter Nielsen. A Kamehameha butterfly adorned the 2016 award.

tributed to keeping Maui free from invasive species. Examples include: not selling or using invasive plants; steps taken to learn about invasives; and efforts to reduce use of invasive species by other customers.

Applications are due by Friday, June 1st, 2018 and are available here: 2018 Malama i ka `Aina Award On-line Application

You may submit completed nominations via  email to miscpr@hawaii.edu, fax to 573-6475, or mail to MISC at P.O. Box 983, Makawao, HI 96768. There is no fee to apply. Self-nominations are welcome.  For more information, call 573-MISC (6472), or e-mail miscpr@hawaii.edu.

Past Malama i ka Aina Award recipients were recognized for meaningful steps taken to prevent the spread of invasive species, including incorporating codes-of-conduct in business practices, educating the public and clients about invasive species, and encouraging the use of native species in landscape design. Actions of award recipients are steps in the right direction!

Filed Under: Get Involved!, Malama i ka Aina Award Tagged With: landscaper award, malama i ka aina award

Natural enemies could tame invasive Himalayan ginger

Posted on April 23, 2018 by Lissa Strohecker

Though not invasive in India where it is native, Himalayan ginger can completely transform a Hawaiian rainforest as it has in this section at a 4,000-foot elevation above Haiku. Ginger fruits can be spread long distance by birds and rats. — FOREST and KIM STARR photo.

The subtropical rainforests in the foothills of the Himalayan Mountains are amazingly diverse. In sections of India and Nepal, the forests are similar to Hawaiian rainforests in both temperature and rainfall-but the flora and fauna are radically different: this is the land of elephants and red pandas; 600 species of butterflies live here and over 400 species of orchids. But amongst the exotic plants, there is one that might be familiar to residents of Hawai’i-a yellow-flowered ginger that covers vast sections of Hawaiian rainforests.

Himalayan ginger, Hedychium gardnerianum, is native to the Himalayan foothills. There, it evolved over millennia supporting a diversity of species: the sweet nectar is feed for the long-tongued butterflies of the region and the plant lives in harmony with the species that surround it. Yellow flower stalks dot the landscape amongst hundreds of other orchids, gingers, ferns, and trees.

But in Hawai’i, Himalayan ginger dominates the landscape-growing fast and paving its way into the forest in an unrelenting march. “Himalayan ginger displaces critical native vegetation layers, limits canopy tree recruitment, and hogs water resources in their massive rhizomes (roots). As it takes over and forms monotypic stands, it negatively impacts native flora and fauna, including Hawai’i’s unique arthropod complex and the Hawaiian honeycreepers,” says Alison Cohan, director of the Maui Nui Forest Program with The Nature Conservancy (TNC).

Djami Djeddour, weed biocontrol scientist with the Centre for Agriculture and Bioscience International, inspects a lone Himalayan ginger plant in India while searching for insects and fungi that live on the plant where it is native. These insects may be responsible for keeping the plant in check. — DJAMI DJEDDOUR photo.

Introduced as ornamental, Himalayan ginger escaped backyards and began invading rainforests of East Maui in the mid-1950s. With seeds dispersed far and wide by birds and rats, the weedy plant spreads by leaps and bounds into the forest. Today, much of the mid-elevation rainforest of East Maui is a patchwork of native forest and alien ginger. But there is a lot left to protect: many ginger-free areas remain, including most of West Maui. 

Ginger is a formidable foe and removing the plant is no simple task. Roots pave the forest floor like asphalt and every part of the rhizome must be removed. Bagged rhizomes take years to decay and if there is the slightest hole in the bag, hardy shoots emerge. If using herbicide, every portion of the root has to be treated. Plants on steep slopes and cliffs are inaccessible and impossible to remove until the weight of the water-logged roots causes entire sections to collapse in a landslide. Why would ginger be a pest in one place but not another?

Invasive Himalayan ginger taking over the east side of Maui. Ginger fruits can be spread long distance by birds and rats. — FOREST and KIM STARR photo.

The answer to that question is on the minds of resource managers in Hawai’i as well as New Zealand, Australia, and South Africa where the plant is invasive. With funding from organizations like TNC and the Hawai’i Invasive Species Council, research scientists traveled to India and collected insects and fungi that live on Himalayan ginger hoping to discover what keeps the fast-growing herb in balance there. An effective natural enemy could be a game-changer for Hawai’i.

An effective natural enemy wouldn’t eliminate the plant, just bring it into harmony with the surrounding environment, much like it is in India and Nepal. One of the most promising insects is a Cloropid fly that lives only on Himalayan ginger. The larvae live inside the stem stunting the growth and reducing flower production. Ginger natural enemies may be ready for release in New Zealand soon, promising progress for Hawai’i.

“An effective natural enemy wouldn’t eliminate the plant, just bring it into harmony with the surrounding environment, much like it is in India and Nepal.”

“The Nature Conservancy had been doing ginger work in Waikamoi for over 30 years, systematically conducting ginger control—containing the core population at the western edge of Waikamoi and eradicating outliers in native forest,” explains Cohan. Crews with Haleakalā National Park work on the flowering pest in Kīpahulu Valley but the plant is widespread and thrives unchecked in wet places throughout the state. 

There are ways you can help. Consider what you call the plant: though known for years as kāhili ginger, a pest destroying the rainforest does not deserve a moniker reminiscent of Hawaiian royalty much less one that might suggest that it belongs here. Perhaps call it toilet-brush ginger, as suggested by Pat Bily of TNC after years of removing it. Do not plant Himalayan ginger in your yard and remove it from your property before it spreads. Finally, participate in The Nature Conservancy’s quarterly volunteer trips removing ginger from Waikamoi Preserve. Contact hike_waikamoi@tnc.org if interested.  

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 April 3rd, 2018, as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.

Read more Kiaʻi Moku articles.

Filed Under: Kia'i Moku Column Tagged With: 2018, biocontrol, ginger biocontrol, Himalayan ginger

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Maui Invasive Species Committee (MISC)
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