Lissa Strohecker — Page 14 — Maui Invasive Species Committee (MISC)

Ants and Hawaiian Seabirds – A Deadly Combination

Posted on November 9, 2012 by Lissa Strohecker 3 Comments

The Hawaiian archipelago is crawling with ants and not a single one belongs here. Humans

A petrel is covered by big-headed ants on Kure Atoll. While ants can be a nuisance for people, the insects can maim or kill nesting seabirds.
SHELDON PLENTOVICH photo

introduced over forty-five ant species to the islands. While they’re a nuisance to people, to Hawaiian seabirds they are a major problem.

Sheldon Plentovich is the Coastal Program Coordinator with the Pacific Islands Fish and Wildlife Office. She has studied some of these impacts. “Seabirds nesting in Hawaii do not have effective defenses against dense supercolonies of invasive ant species,” she says. And even though high densities of invasive are present, the seabirds return to the same areas to nest as they have for generations.

In March, throughout Hawai‘i, Wedge-tailed Shearwaters dig burrows for nesting along the coastline. Unfortunately tropical fire ants, Solenopsis geminata, often inhabit these areas. Plentovich isn’t sure whether the ants are trying to eat the birds or if the ants are just defending their nest. Adult birds can fly away to escape the ants but the chicks can’t. “They’re programmed to stay in the nest,” explains Plentovich. In their fury, the six-legged invaders destroy the tender webbing on the chicks’ feet. These ant attacks affect the development of the chicks as well. Oftentimes chicks that have been attacked fail to grow feathers.

Plentovich knocked back the population of tropical fire ant on one islet off the coast of O‘ahu and, as expected, found that the seabirds had greater fledgling success compared to those on an islet still infested by tropical fire ant.

Tropical fire ants attack a wedge tailed shearwater chick on islet off Oahu. These attacks can permanently disfigure birds’ feet and even lead to chick’s death. Photo Sheldon Plentovich

Tropical fire ants belong to a group designated as “tramps.” Tramp ants are omnivorous, and because they do not compete between colonies, form dense supercolonies made up of multiple queens. These dense supercolonies can outcompete everything else for food and resources. And since it takes a queen to start a new colony, the greater density of queens makes it easier for these ants to be spread around by people. Not surprisingly tramp ants include some of the Pacific’s most devastating invasive species, such as the little fire ant. They’ve hitched rides to the furthest reaches of the Hawaiian archipelago.

Johnston Atoll is one of the most isolated atolls in the world, 860 miles west of Hawai‘i. The Atoll is strictly a wildlife refuge where red-tailed tropicbirds nest alongside shearwaters, petrels, terns, noddies, and boobies. Unfortunately the atoll has become a haven for the yellow crazy ant or Anoplolepis gracilipes. This tramp ant doesn’t bite or sting the birds, rather it sprays them with formic acid and birds don’t respond well to formic acid. Animals that can seek out fish from the sky are left with swollen puffy eyes. Plentovich has seen Red-tailed Tropicbirds that have “toughed it out” staying to nest despite being swarmed by ants, spraying formic acid.

Footage of a Red-tailed Tropicbird swarmed by yellow crazy ant on Johnston Atoll. These invasive ants swarm nesting seabirds. Seabirds show high nest fidelity and return to the same location to rear their young despite the presence of these ants. Video by Sheldon Plentovich

Ants impacts can vary from place to place. The big-headed ant, Pheidole megacephala, is one of the most common ants in Hawai‘i. On Moku‘auia off Oahu, eradicating big-headed ant had no effect on the hatching and fledging success of shearwater chicks.

Big-headed ant attacks Bonin Petrel chick on Kure Atoll. Big-headed ants are one of the most common ants in Hawaii but on Kure the population reached such a high density the ants were attacking everything in sight. Photo by Cynthia Vanderlip

But on Kure Atoll the big-headed ant has been seen swarming birds and eating chicks alive. Plentovich thinks ant density is the reason. On Kure, the population of big-headed ants was 5 times more dense than it ever was on Moku‘auia. “They’re eating everything they encounter,” says Plentovich.

Chances are people inadvertently brought ants to isolated Johnston and Kure Atolls. All it takes is a single queen ant in a piece of cargo to start an infestation. And eradicating an established infestation is extremely difficult work. Plentovich is hopeful that new techniques will lead to the eradication of yellow crazy ant on Johnston atoll where other techniques have been unsuccessful. She’s seen how controlling an invasive ant can influence the whole ecosystem. When she reduced the population of invasive ants on offshore islets she saw an increase in the diversity of insects and “native plants survived better-the ‘ilima started taking off.”

By Lissa Fox Strohecker. Originally published in the Maui News, October 14th, 2012 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.
You can find all the articles in the Kia‘i Moku series http://www.hear.org/misc/mauinews/

A hidden world in Maui’s streams

Posted on October 12, 2012 by Lissa Strohecker 1 Comment

After 27 years of working with the Department of Land and Natural Resources, aquatic biologist Skippy Hau has become pretty familiar with Maui’s streams and the creatures dwelling in them. But there are always surprises. Several years ago, Hau discovered hīhīwai, one of two species of native Hawaiian freshwater snails, crawling single file up the cement bottom of a channeled stream next to a West Maui grocery store. The stream is typically dry, with few rocks to shelter the hīhīwai, but there they were.

This hīhīwai, a native Hawaiian snail, clings to a rock in a Maui stream. The presence of slow-movnig hīhīwai can indicate the frequency and quantity of water needed for a healthy stream.

It’s amazing that Hawaii has any native freshwater species to begin with. Streams in Hawai‘i are 2,400 salty miles away from the nearest continental sources of freshwater. Yet fish, crustaceans and mollusks colonized island waterways well before the first Polynesians arrived, most evolving into species found no where else in the world. These animals have evolved to cope with intermittent stream flow and climb waterfalls. ‘Ōpae kala‘ole, an endemic crustacean, is the best climber of all, known to scale 100-foot cascades. But like other native Hawaiian plants and animals, these riparian creatures now face threats from introduced species.

Invasive armored catfish have added the eggs of the native ‘o‘opu (goby) to their diet. Guppies and mosquito fish devour Hawaiian stream dwellers’ larvae and contribute to the decline of native damselflies at low elevations. Swordtails and other non-native aquatics spread new diseases to native fish. Tilapia compete with native water birds for food and released pet turtles dine on ‘o‘opu.

‘O‘opu nōpili. Photo by Skippy Hau

‘O‘opu nākea in ‘Iao stream. Photo by Skippy Hau

‘O‘opu ‘alamo‘o. Photo by Skippy Hau

Most of these invasive species were intentionally introduced – starting with Asian immigrants bringing in Chinese catfish, rice-paddy eels and other species for food in the 1800s. Mosquito fish, or topminnows, were released into streams from the 1900s through 1960s to control mosquitoes. This was an era when state officials frequently introduced game species, such as trout, bass and tucunare, or peacock bass, into streams. During the 1970s, managing resources for native species became more important; game fish are no longer introduced.

In the 1980s and ’90s, aquarium fish and mollusks began appearing in Hawaiian streams. In addition to guppies and swordtails, a variety of cichlids and ramshorn snails now snack on larvae of native stream animals returning to the ocean. Aquarium owners who dump unwanted pets are the most likely source of this problem, which is ongoing.

Hīhīwai, like all Hawaiian stream dwellers, are only part-time residents. They spend the first year of life in the ocean, then ascend single file into a freshwater stream. Not all make it as they colonize the stream’s upper reaches, instead becoming a source of food for other riparian species. In addition to the hīhīwai, another native mollusk, five species of fish and two crustaceans spend a part of their lives in the ocean. During rare flood events, these freshwater animals move quickly upstream for the less salty part of their lives, finding shelter in upper elevation pools.

Hau regularly monitors the slender tributary of ‘Iao where he first witnessed the climbing snails. When it exceeds a trickle, he dons a snorkel mask and peers under rocks for slow-moving hīhīwai. By carefully studying Maui’s streams, Hau has documented the frequency and volume of water necessary for our native freshwater animals need to move between ocean and stream.

These remarkable aquatic animals need our help. Don’t release unwanted pets into streams. If your fish is too large for your aquarium, contact a local pet store. They often take back fish and snails. Consider selling or gifting your unwanted fish or turtle online or to a friend.

Learn more about the fascinating animals in Hawaii’s streams and how to help protect them at hawaii.gov/dlnr/dar/streams.html.

By Lissa Fox Strohecker. Originally published in the Maui News, June 10th, 2012 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.
You can find all the articles in the Kia‘i Moku series http://www.hear.org/misc/mauinews/

Know an invasive-species-savy landscaper or nursery?

Posted on September 24, 2012 by Lissa Strohecker Leave a Comment

The Maui Association of Landscape Professionals, Maui Invasive Species Committee, and the County of Maui will recognize a professional landscaper, plant provider, or commercial/agricultural property owner’s efforts to protect Maui County from invasive species.

The 10th Annual Mālama i ka ‘Āina Award winner will be announced at the MALP Lawn and Garden Fair, November 3rd, at the Maui Mall. Nomination forms are available below or by calling 573-MISC or visiting www.mauiisc.org or www.malp.org.

Application Deadline is Saturday October 20th.

2012 Malama i ka `Aina Award On-line Application

2011 Malama i ka Aina Award Winners Elaine Molina and Sarge McBride (center with plaque and lei) and presenters (from left to right) Rob Parsons with the County of Maui, Teya Penniman and Pat Bily with MISC, and Gary Mohrlang with the Maui Association of Landscape Professionals.

2010 Malama i ka Aina Award Recipient Mach Fukada

The ‘Ua‘u and the threat of invasive species

Posted on September 13, 2012 by Lissa Strohecker Leave a Comment

Hawai‘i is famous for rare birds: scarlet honeycreepers that dart through the rainforest and gold-flecked owls that hunt at twilight. But another Hawaiian bird lives most of its life at sea. The ‘ua‘u , or Hawaiian petrel, returns to land under the cover of darkness—and then only to nest. Now is the time to be on the look out for this cryptic bird; the chicks are fledging.

An ‘ua‘u chick hides in his burrow awaiting his parents return. In the meantime the chick is vulnerable to passing rats, cats, and mongoose who can quickly scoop the chick from his hiding place.Photo by Jay Penniman

Named for their eerie nighttime call, “uuua-uuuu,” the ‘ua‘u alight on land for only a few minutes before ducking into their underground burrow. Their nesting locations are remote, difficult to access. Counts at sea estimate the population at around 20,000, low enough to earn a place on the Federal Endangered Species list.

Fossils indicate that ‘ua‘u were once so plentiful in Hawai‘i they blackened the sky. Prior to humans’ arrival in these Islands, ‘ua‘u and their feathered friends ruled these Islands. ‘Ua‘u built burrows from the coastline to the mountaintop, digging into soil and taking advantage of existing crevices. But populations have dwindled to a fraction of what they were, due to habitat loss and predation. Now invasive species threaten to overrun the sliver of habitat remaining for native birds, while predators lurk outside their burrows.

Having evolved without mammalian predators, ‘ua‘u are particularly naïve, both in their choice of nesting location and how they rear their young. Ground nesting, even in a burrow, leaves petrel chicks and eggs vulnerable to attacks by stealthy rodents or felines. Pigs, goats, cattle, deer, and people trample burrows, crushing the egg or the chick inside.

‘Ua‘u only lay one egg per season, and both parents invest much energy and effort in rearing the chick. A trip to the grocery store for an ‘ua‘u parent is a two-week, 6000 mile journey along the northwest Hawai‘i an islands to the Aleutians and circling back down to Hawai‘i , among the longest feeding routes of any known seabird. Unfortunately, there is no babysitter; the chick’s safety depends on remaining underground, hidden from predators.

While the species as a whole demonstrates remarkable flexibility in choosing nesting sites—from dense thickets of uluhe fern to frigid cliff faces on the summit of Haleakalā –individual birds are guided by habit. They return to the same burrow year after year, despite the likelihood of a cat laying in wait.

Many people are working to protect the ‘ua‘u . Biologists arelearning more about these remarkable birds by observing their burrows and tracking their movements. A major colony was re-discovered on Lāna‘i in 2006, but the birds’ native habitat was being choked out by invasive trees. To protect this colony, staff from the Lāna‘i Native Species Recovery Program and volunteers are fighting back acres of strawberry guava and replanting the uluhe fern that form a protective blanket over the burrows. Within Haleakalā National Park, park staff controls predators that attack ‘ua‘u .

‘Ua‘u, like this one, are often disoriented by streetlights and end up on the ground. If you find an ‘ua‘u safely pick it up and call the Maui Nui Seabird Recovery Project, (808) 280-4114. Photo by Jay Penniman

You can help as well. When petrel chicks leave the burrow for their first time they can become disoriented by the bright lights of civilization. Some birds come crashing down onto buildings or roads. A grounded chick is defenseless against predators and threatened by cars. If you see a petrel on the ground, carefully pick it up with a cloth or towel and place it in a well ventilated box. Do not try to feed the bird. Call Maui Nui Seabird Recovery Project (808) 280-4114.

By Lissa Fox Strohecker. Originally published in the Maui News, September 9th, 2012 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.
You can find all the articles in the Kia‘i Moku series http://www.hear.org/misc/mauinews/

Fast-growing ivy gourd threatens rare dryland ecosystem on Maui

Posted on August 23, 2012 by Lissa Strohecker Leave a Comment

Ivy gourd can be identified by the 5-petaled flowers and green fruit that turn red as they ripen, hanging like Christmas lights from the plant. Photo by MISC

On Maui, we are lucky to have so many open spaces. Our island is relatively undeveloped, though you may beg to differ when you’re stuck in traffic. The majority of the population lives along the coastlines. This distribution of island residents is nearly identical to the distribution of ivy gourd; a highly invasive vine found growing in central, south, and west Maui. And, as development expands, so does the population of ivy gourd. This is no coincidence.

Native to Africa, India, and Southeast Asia, ivy gourd was probably brought to the Hawaiian Islands by an immigrant from one of those areas. The immature fruit of the plant, as well as the young shoots, are used in cooking. Many recipes from Southeast Asia call for ivy gourd. While it may taste good in a stir fry, it’s in poor taste—illegal even—to have the plant growing in your yard.

Inevitably, the vine escapes cultivation. Humans—and their pesky rodent counterparts—have been the vectors for spreading ivy gourd. Rats scamper off with a stolen fruit spreading the seeds. In absence of the insect pests that limit ivy gourd’s growth in its native habitat, the plant grows unchecked. Roots form every time the branching vine touches the ground. Each root is enlarged, giving ivy gourd the ability to survive lengthy periods of drought.

Ivy gourd, Coccinia grandis, can be hard to identify without the flower or fruit present. The leaves are broad and flat, shaped like an angular heart, about 2.5 inches wide. They are arranged in an alternating pattern along the vine. The flower is white, with 5 petals curving out of a tube-like base. If the plant reaches the fruiting stage, the 3-inch long fruit, dangling like bright red Christmas lights, is a dead giveaway that the vine smothering your yard is ivy gourd.

Ivy gourd is fast-growing. While we don’t know the actual rate of growth on Maui, it is a member of the cucumber family of plants that may grow up to 4 inches a day. If we ignored this aggressive growing vine what would happen? “We’d be ivy gourdians” a 7^th grade student so aptly replied during a class visit by MISC. When people don’t consume ivy gourd, ivy gourd consumes the environment around us. Trees, power poles, fences, even cars disappear beneath a mountain of vines.

The fast-growing ivy gourd can easily smother trees, fences, and power lines. It could transform the native dryland ecosystem, choking out rare Hawaiian plants and leaving nothing but curtains of green. Photo by MISC

Ivy gourd is currently limited to residential areas on Maui. MISC’s successful control of the population depends entirely on the cooperation of property owners and residents. Because the vine grows so fast, and because the seeds germinate so quickly after a rain, monthly site visits may be necessary. A plant can go from seedling to seed-bearing within as little as a month, and once the plant produces seed, the seed bank can last for years. Field crews must find and apply a few drops of herbicide to every single root in order to kill the plant, no small task when the plant has covered several kiawe trees.

On the islands of O`ahu and Hawai’i, ivy gourd is invading natural areas. On Guam and Saipan, ivy gourd is so established that the only way to limit it may be through biocontrol. Insect pests have been released in these areas. On Maui, control efforts have reduced ivy gourd to a level that would no longer support a viable biocontrol population. The only way to eradicate it is to get rid of the remaining plants, monitor locations for new plants, and prevent new introductions.

If a plant nursery is infested with ivy gourd, it’s almost inevitable that seeds and plant material will be spread in contaminated soil. This may help explain why we find ivy gourd in golf courses. A huge infestation was discovered on Lāna‘i in 2006, and with continued effort the population is being knocked back.

And those open spaces on Maui? Above the development of Lahaina and Kīhei are the remnants of the native dryland forest ecosystem. The leeward slopes of Haleakalā, where this ecosystem was once predominant, still harbor stands of native trees. This is where ‘iliahi (sandelwood) grows. The wiliwili tree can be found here, as well as the naio trees that gave us the name for the area: Kanaio. These areas have been greatly altered by ranching and the introduction of goats and deer, yet they still include rare native plants and insects. There is no ivy gourd here. Ivy gourd would thrive here if introduced into these native forests. Ivy gourd would smother the existing vegetation, leaving curtains of green where there once were diverse and rare ecosystems.

Help us protect these rare ecosystems on by finding and reporting ivy gourd in Maui’s residential and rural areas. Do not grow ivy gourd. If you suspect you may have ivy gourd on your property, please call the Maui Invasive Species Committee at 573-MISC (6472) and we will remove it, free of charge.

The nose knows: dogs sniff out invasive species

Posted on August 16, 2012 by Lissa Strohecker Leave a Comment

A beagle with the U.S. Customs and Border Protection inspects passengers luggage in an airport. The Hawaii Department of Agriculture has done similar work with dogs in the past; a recent bill passed by the Hawaii State Legislature will help bring the program back. Photo by James Tourtellotte.

This fall there will be some new faces at the Hawai‘i Department of Agriculture (HDOA)– furry faces. The Hawai‘i Detector Dog Program is returning, thanks to restored funding from the state legislature and matching federal funds. Alongside their human handlers, these four-legged inspectors will screen incoming cargo and luggage on O‘ahu to help prevent plant and animal pests from becoming established in Hawai‘i.

Hawai‘i’s detector dogs will be sniffing for brown tree snakes that may have stowed away in shipments from Guam, but they will also inspect other cargo arriving at both the Honolulu airport and O‘ahu military bases, including mail and parcel shipments.

The 20 year-old program was cut in 2009 due to a lack of funds. Prior to the program’s demise, busy beagles and handlers bagged seven snakes in a 14-15 year period. During inspection blitzes at the Maui airport, dogs uncovered more than a thousand instances of undeclared produce and vegetation, including a shipment of persimmons infested with mealybugs not known to be in Hawai‘i. Hawai‘i’s airport dogs also serve as ambassadors for HDOA, letting passengers know with a friendly wag that their luggage was inspected behind the scenes as well as in the baggage claim area.

The new inspectors will be in good company. Man’s best friend, long called upon for helping humans in search and rescue, hunting, and police work, now is lending a nose on a variety of conservation fronts.

Kristine Lesperance and Dexter hunt the invasive rosy wolf snail in the Waianae Mountains of Oahu. Photo by Oahu Army Natural Resource Program.

Kristine Lesperance of O‘ahu Detection Dog Services and her lab-mix named Dexter have been working hard to save native Hawai‘i an tree snails, or Achatinella,in the Wai‘anae Mountains. Dexter sniffs out invasive animals that prey on native tree snails: the cannibalistic rosy wolf snail and Jackson’s chameleon. Dexter can distinguish between a rosy wolf snail, a giant African snail, and native snails by scent. When he finds one, he sits down and waits for his reward. He can track chameleons by the smell of their scat, a definite advantage for finding these cryptic creatures.

Lesperance says dogs are great for determining the presence or absence of an animal across large areas. Depending on the species the dog is searching for and how odoriferous it is, it may take awhile. With the rosy wolf snail, Dexter doesn’t cue into the scent until he’s one-half inch to two inches from the snail, taking up to 30 minutes to find one; he does better with Jackson’s chameleon scat, finding it from several feet away, but, when working as a search and rescue dog, Dexter can smell a person a quarter mile away.

In Missoula, Montana, trainer Dalit Guscio is about to reward Seamus. He’s been tracking down invasive Dyers woad plants. Seamus and Dalit are with the Montana-based Working Dogs for Conservation. Photo by Elizabeth Stone.

In Montana, dogs are sniffing out invasive plants in the field, outperforming their human counterparts at finding scattered small plants. Elsewhere, dogs are finding bees, pythons, rare plants, cane toads, tortoises, termites, and even root fungus. “I think we could use dogs to find pretty much anything that has a scent,” Lesperance says, adding that further work will help determine how dogs can be most effective in different conservation scenarios.

Although dogs have been trained to help in conservation for 10-15 years, “we’re really just seeing the beginning” says Lesperance. Our new four-legged recruits will help close gaps in agricultural inspection, but many opportunities exist for canine eco-detection services. Who knows whose nose will be hard at work protecting Hawai‘i?

By Lissa Fox Strohecker. Originally published in the Maui News, August 12h, 2012 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.
You can find all the articles in the Kia‘i Moku series http://www.hear.org/misc/mauinews/

A changing climate and the plight of the ‘i‘iwi

Posted on August 6, 2012 by Lissa Strohecker Leave a Comment

An adult ‘i’iwi sips nectar form the flowers of a native lobelia in the Waikamoi preserve. The habitat for the i”iiwi and other Hawaiian honeycreepers is threatened by climate change. As climate warms mosquitoes that transmit disease to the native birds will increase in range. Photo by Forest and Kim Starr

On just about any given day you can find ‘i‘iwi, among the more charismatic species of Hawaiian honeycreepers, flitting around Hosmer’s grove, just past the entrance to Haleakalā National Park. These energetic little bursts of red flit from tree to tree feeding on the nectar of ‘ōh‘ia flowers and the occasional spider or insect. Once abundant on all islands from sea level up into the mountains, these brilliant birds are now rarely seen lower than 5000 feet. Below that elevation, avian malaria, a bird disease transmitted by mosquitoes, has decimated Hawaiian honeycreepers. Today, even the birds subsisting in the high-mountain pockets of habitat are threatened—not only by invasive plants and animals, but also by climate change.

Avian malaria is not new in Hawai’i. Migratory birds carrying malaria regularly visited Hawaiian shores—but before mosquitoes were introduced, the disease had no way to infect resident bird populations. In 1826, sailors on the whaling ship Wellington dumped barrels of mosquito-infested water into a Lahaina canal. That marked the beginning of the end for low- and mid-elevation native honeycreepers.

Since then, mosquito-born diseases have caused two major waves of extinction in Hawaiian honeycreepers. Native forest birds have shown scant resistance to foreign diseases. Those that survive inhabit forests above the “mosquito line,” where neither mosquitoes nor the diseases they carry can thrive. In cooler temperatures, avian malaria can’t reproduce fast enough to infect birds. Thus the largest populations of ‘i‘iwi dwell in the cloud forests of East Maui and Hawai’i; the birds are increasingly rare or nonexistent on islands without tall mountains. ‘I‘iwi have vanished from Lāna‘i and only a few remain on Moloka‘i and West Maui. With a warming climate, the remnants of disease-free habitat may shrink or disappear.

Introduced mosquitoes transmit avian malaria and pox from non-native birds to native birds.

Introduced mosquitoes, such as the tiger mosquito above, transmit avian malaria and pox from non-native birds to native birds. Having evolved in isolation, native birds lack resistance to these diseases. Photo by James Gathany, CDC

And Hawai‘i is heating up. Each decade since 1975, minimum nighttime temperature has increased an average of almost 1°F. Nighttime temperature is the determining factor in estimated elevational range of avian malaria. Over the last 50 years, the mosquito line has steadily marched up the mountain, from 2000 feet in the late 1960s to nearly 5000 feet today.

Climate change may affect our native birds in other ways. Summer storms are predicted to become more frequent, creating more habitat for mosquitoes during their optimum breeding season, increasing their density and the likelihood of transmission of avian malaria. Meanwhile, overall rainfall may decrease, compromising the health of the native Hawaiian rainforest and the inhabitants that rely on it.

The ‘i‘iwi is not the only bird likely to be chased out of remaining habitat by avian malaria and climate change. In Hawaii all of our non-migratory birds, such as the Maui crested honeycreeper or ‘ākohekohe, Maui parrotbill or kiwikiu, and the ‘apapane, face the same danger. These species are unique among the world’s creatures; they exist nowhere else on earth. Many of them are highly significant to the native Hawaiian culture and all play critical roles in their natural environments. Their loss would be devastating.

In response to concerns raised about the ‘i‘iwi’s perilous situation, the United States Fish and Wildlife Service is proposing to list the ‘i‘iwi as federally threatened or endangered, with climate change noted as a factor in its decline. How can you help? Support efforts to address the causes of climate change. Work to protect the remaining natural areas that shelter ‘i‘iwi. And take a trip to Hosmer’s Grove to witness just how spectacular these winged treasures are.

By Lissa Fox Strohecker. Originally published in the Maui News, July 8th, 2012 as part of the Kia‘i Moku Column from the Maui Invasive Species Committee.
You can find all the articles in the Kia‘i Moku series http://www.hear.org/misc/mauinews/

Moving on from the Mongoose: the Success of Biological Control in Hawai‘i

Posted on April 18, 2012 by Lissa Strohecker 2 Comments

Achieving balance–in your workplace, at home, on your surfboard, or with your checkbook—makes life manageable. Natural environments depend upon balance as well.

Invasive pests have been disturbing the natural balance of Hawaiian ecosystems for centuries, ever since the arrival of the rat with early Polynesian explorers. Bringing invasive species into better balance with the environment is nothing new here in Hawai‘i. An effective biological control, or natural predator, can transform a devastating invasive species into a mild pest.

The invasive Erythrina gall wasp that threatened the native wiliwili trees, such ans this one, was brought into balance by a parasatoid wasp.

The vast majority of biological control efforts in Hawaii have been successful: pānini cactus that once choked pasture land is now checked by three predatory insects and a plant fungus; white loosestrife or pāmakani is continually attacked by two insects and another plant fungus; and recently, the Erythrina gall wasp, that wiped out ornamental coral trees and threatened the native wiliwili with extinction, was leveled by a parasitoid wasp.

Yet, just as impulsive actions sabotage balance in our own lives—think diet fads and over-exercising–the same kind of recklessness results in greater instability in our environment.

Such is the case with the small Indian mongoose, Herpestus javanicus. In 1872, a sugar planter released nine mongoose on Jamaica with the hope it would control rats in cane fields. The planter considered it successful and published a paper about it. Mongoose populations grew and offspring were sold to plantations throughout the Caribbean, Cuba, and Puerto Rico. In 1883, Hawai‘i plantation owners jumped on the mongoose bandwagon. With little regard for potential impacts, the now defunct Hilo Planters Association released seventy-two mongoose from Jamaica in Hilo. Another batch of mongoose from eastern India was brought to the Hāmākua coast in 1885. Subsequent offspring were released on Maui, O‘ahu, and Kaua‘i. For an unknown reason the crate delivered on Kaua‘i was kicked off the dock. To date mongoose have not established on Kaua‘i, though a single female was found killed by a car in 1972.

The mongoose is an opportunistic predator, introduced to Hawaii in 1883 with little regard to potential impacts on species other than the rat. Today, a potential biological control goes through years of testing to ensure it will have no unanticipated impacts.

Mongoose do eat rats, in Hawai‘i and elsewhere, but mongoose are opportunistic predators eating primarily insects, with birds, eggs, and a handful of plants mixed in. Additionally, mongooses are active during the day, rats at night. The introduction of the mongoose further tipped the balance of the environment in the wrong direction: now both mongoose and rats threaten populations of native birds, particularly ground-nesting species like nēnē and petrels.

The mongoose introduction was not an example of classical biological control; it was an impulsive, untested whim. Today, when researchers look for biological controls for a particular pest, they survey the pest’s native habitat for species that counteract the pest’s invasive characteristics. Before any new organisms are introduced in Hawai‘i, they are subjected to intensive testing in quarantine to determine potential impacts on any other species.

Successful candidates for biological control have evolved over millennia alongside their target; some are dependent solely on the target species for survival. For example, the Eurytoma wasp that saved the wiliwili will die without access to Erythina gall wasps. Consequently, Eurytoma populations will stop short of entirely eliminating the Erythrina gall wasp. Rather it will restore balance, keeping the pest wasp in check.

When mongoose were brought to Hawai‘i, there were no restrictions on plant and animal imports. Impacts on other species were an afterthought, if considered at all. It wasn’t until King David Kalākaua enacted the “Laws of the Hawaiian Islands” that any regulation existed to limit the introduction of new species to Hawai‘i.

Government-led pest management didn’t begin until ten years after sugar growers introduced the mongoose. The provisional government appointed Albert Koebele as the chief entomologist, the first of many tasked with preventing new and controlling existing pest populations

Biological control has a long and successful history in Hawai‘i. In fact, California and Hawai‘i lead the world in successful releases of natural predators. Ever since testing of biological controls began, there have been no incidences of “host-jumping” or biological controls attacking other species. Yes, the infamous mongoose ran amok, but it arrived during an “anything goes” era in Hawaiian history. The mongoose–or any opportunistic predator–would never be considered suitable for introduction by today’s standards. Biological controls are an important tool—sometimes the only tool—that can restore balance in Hawaiian ecosystems.

Originally published in the Maui News, April 8th, 2012 as part of the Kia‘i Moku Column.
You can find all the articles in the Kia‘i Moku series http://www.hear.org/misc/mauinews/

Grow bananas? Guard against BBTV.

Posted on March 15, 2012 by Lissa Strohecker 2 Comments

Check for “J-hooks” along the midrib of the of the banana leaf. This is a symptom of BBTV infection. Photo Courtesy of Scott Nelson, UH-CTAHR.

In the spring of 2009, Angela Kepler found a diseased banana plant on her neighbor’s property. “It really freaked us out! As soon as we found out we ran next door and sprayed for aphids.” The neighbor’s banana plant was infected with banana bunchy top virus (BBTV). “BBTV is the worst,” Kepler explains. “Now we help check everyone in the neighborhood.”

Angela Kepler and Frank Rust study bananas. Of the 32 different kinds on their property, most are rare Polynesian bananas collected from the wild or someone’s backyard. They photograph and observe each plant from keiki to fruiting to learn the key characters that make each type unique. Kepler and Rust are writing a book on how to identify different types of bananas. They know what BBTV can do.

The plant on the left is infested with BBTV. Note how the new growth is bunched together, a symptom that gives the disease its name. Photo courtesy of Scott Nelson, UH-College of Tropical Agriculture and Human Resources

BBTV is the most serious known disease of bananas. Infected plants produce shrunken, malformed leaves and distorted fruit—if they fruit at all. BBTV eventually kills all plants in an infected mat (root mass)there is no cure for the disease. Removing infected plants and preventing spread is the only control for BBTV—a necessary precaution if bananas are to continue being grown in Hawaii. BBTV threatens the banana industry, backyard farmers, and rare, culturally significant banana varieties, such as those grown and collected by Kepler and Rust. “We’ve seen a tremendous demise in the last 10 years,” says Kepler.

BBTV is spread between plants by banana aphids. The virus is passed from an infected plant to the aphid and transmitted when the aphid feeds on a healthy plant. People then spread BBTV great distances when they transport infected plants. Anyone who moves or harbors infected plants puts their neighbors’ plants at risk.

Banana bunchy top virus is widespread in Southeast Asia, the Philippines, Taiwan, the South Pacific, and in parts of India and Africa. It was first discovered in Hawaii in 1989. BBTV is widely established on O‘ahu and has been detected on Hawai‘i Island, Kaua‘i, Maui, and Moloka‘i. “We haven’t been able to collect bananas from other islands, or share ours due to BBTV,” says Kepler.

On Maui, backyards in Kīhei and Pukalani suffer the densest infestations of the disease. Banana farms in Kula and, most recently, central Maui have been wiped out. Not surprisingly, BBTV thrives in Lahaina as well; drier climates are better aphid habitat. Scattered infestations of BBTV have been found in Ha‘ikū and Huelo as infested material has been brought into the area. To date, Hāna, Ke‘anae, and Kipahulū are free of BBTV.

Another indication of BBTV infection is a sporadic dark green streaking, as if in a Morse-code pattern along the leaf sheath. MISC file photo.

Controlling and preventing the spread of BBTV is everybody’s business. If you have banana plants check them regularly for symptoms of the disease. Initial signs of infection are: 1) dark “Morse code” streaks along the leaf stem named for the irregular pattern of dashes and dots along the veins, 2) “J-hooks’ where the leaf veins along the blade of the leaf curve into the midrib. As the infection becomes established, new leaves emerge with difficulty, giving the plant the appearance of having the “bunchy top” that the disease is named for. New leaves are narrow and lance-shaped, often with yellowing around the leaf edges. Plants will stop producing fruit after infected and any keiki from the infected mat are severely stunted.

Check for “J-hooks” along the midrib of the of the banana leaf. This is a symptom of BBTV infection. Photo Courtesy of Scott Nelson, UH-CTAHR.

Controlling the spread of BBTV requires control of the vectors: aphids and movement of infected plants. Regularly spraying your plants with soapy water controls the banana aphid and can help prevent infection. The Maui Invasive Species Committee can help you identify infected plants and will control them for you. Infected plants should be killed on site and left standing until completely dead, typically within six months of treatment. Removing infected plants reduces spread of BBTV; aphids won’t feed on infested plants. Healthy bananas can be replanted in the same place after the mat has completely died.

If you suspect your banana plants are infected with BBTV and live in Maui County, call the Maui Invasive Species Committee at 573-6472. Due to the risk of BBTV, banana plants should not be moved between communities. “We all want to share bananas. People want to give each other plants, but don’t bring bananas from O‘ahu, Hawai‘i Island, or Kaua‘i,” cautions Kepler. “And whatever you do, don’t take bananas to the Hāna and Kipahulu area.”

Article by Lissa Fox Strohecker

Originally published in the Maui News, February 13th, 2011 as part of the Kia‘i Moku Column.
You can find all the articles in the Kia‘i Moku series http://www.hear.org/misc/mauinews/

Native plant growers throughout Hawai‘i replace IHOP’s “The Lorax” themed seed bookmarks with native plants

Posted on March 12, 2012 by Lissa Strohecker Leave a Comment

From March 9th, 2012 press release

HONOLULU — Hawai‘i theater goers enjoying the new movie, “Dr. Seuss’ The Lorax,” and its theme of protecting local tree species can help honor that message by supporting the use of native Hawaiian plants rather than non-native species.

To that end, the Department of Land and Natural Resources (DLNR) worked with local IHOP managers and the IHOP corporate headquarters in California last week to voluntarily discontinue the distribution of promotional bookmarks embedded with seeds at Hawai‘i IHOP locations.

‘A‘ali‘i, or Dodonaea viscosa, is one of the Hawaiian plants being offered in exchange for pine-seed laced bookmarks. ‘A‘ali‘i range in size from shrubs to small trees such as this one at Maui Nui Botanical Gardens. Photo by Forest and Kim Starr

“Thanks to the quick action of DLNR and others involved, we have turned a potentially negative situation into a positive one by expanding on the movie’s underlying message of being better stewards of our natural environment,” said Governor Neil Abercrombie. “The collaborative effort to discontinue the distribution of spruce seeds engages those who may not be aware of the importance of the ‘right plant in the right place.’ Our forests will thrive with more native flora and that benefits all of us.”

The bookmarks are part of a promotional campaign for Universal Pictures’ new movie release, “Dr. Seuss’ The Lorax,” in which IHOP customers are being encouraged to help the Lorax by planting trees. The bookmarks are embedded with Engelmann spruce seeds, which are native to parts of the U.S. mainland but not to Hawai‘i.

IHOP in Hawai‘i has voluntarily discontinued distribution of seeds, and the DLNR and the Coordinating Group on Alien Pest Species have partnered with native Hawaiian plant nurseries to create an exchange program so that any Hawai‘i resident IHOP customers who may already have received a seed-laden bookmark can exchange their spruce seed bookmark for a free native Hawaiian plant.

While the specific species included in the bookmark may not pose a high risk to Hawai‘i’s native plants, other species of spruce trees have been observed to be invasive in parts of the Pacific, where they replace native plants and the animals that depend on them.

IHOP’s corporate office demonstrated its commitment to protecting the environment by also discontinuing this promotion in Puerto Rico and the U.S. Virgin Islands, where Engelmann spruce is also a nonnative species.

“We want to be responsible caretakers of our environment. When we learned that the trees in question would not be the best choice for Hawai‘i, we responded quickly. We hope our guests will take advantage of this exchange opportunity,” stated Patrick Lenow, spokesman for IHOP Restaurants.

First published in 1971, Dr. Seuss’ The Lorax is a fictional story of a pristine environment where truffula trees provide food, clean air, and habitat for a community of unique animals. As they are overharvested to extinction, the Lorax tries to point out the environmental importance of the trees, but to no avail. The animals leave and the environment is left in ruins. However, the end of the story is one of hope: replant the truffula trees to restore the environment.

A close-up of ‘a‘ali‘i fruit showing their distinctive shape and color. Photo by Forest and Kim Starr

“Updating the message of The Lorax to include the value of native species is key for the next generation of conservationists to understand the problems facing our environment,” said Joshua Atwood, coordinator for the interagency Hawai‘i Invasive Species Council housed at the DLNR.

“An important part of The Lorax story is that the truffula trees grow nowhere else, and the Lorax is there to protect that limited resource. Similarly, many of Hawai‘i’s native plants and animals only exist on these islands, and we need to do what we can to protect them. That includes planting native, rather than nonnative, species whenever possible.”

One of the nurseries providing plants for the exchange is Hui Ku Maoli Ola, the largest native Hawaiian plant nursery in the state. “We believe in the importance of perpetuating our native flora as a part of our unique culture and environment,” said Matt Kapaliku Schirman, Hui Ku Maoli Ola co-founder. “This is a great opportunity to help protect and restore the Hawaiian environment.”

DLNR also thanks the Native Nursery and Big Island Plants or Ku ‘Oh‘ia Laka, whose exchange agreements were facilitated by the Maui and Big Island Invasive Species Committees.

IHOP customers who received a Lorax bookmark can exchange the seed-embedded bookmark for a native Hawaiian plant free of charge through the end of April, 2012 at the following participating nurseries:

O‘ahu:
Hui Ku Maoli Ola Native Plant Nursery
46-403 Haiku Rd, Kane‘ohe, HI, 96744
Hours: Monday-Friday 7:30 a.m. – 4 p.m., Saturday 7:30 a.m. – noon, closed Sunday
Contact: (808) 235-6165, www.hawaiiannativeplants.com

Maui:
Native Nursery and Ho‘olawa Farms, exchange facilitated by the Maui Invasive Species Committee (MISC)
Contact MISC at (808) 573-6472

Hawai‘i Island:
Big Island Plants or Ku ‘Oh‘ia Laka, exchange facilitated by the Big Island Invasive Species Committee (BIISC)
Contact: BIISC at (808) 933-3345

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