DOMESTIC QUARANTINE
This week’s article examines the various pests that are present in some parts of Fiji and not in others. Biosecurity Authority of Fiji (BAF) is meticulously working on preventing the spread if these pests to areas that are free of them.
Taro (Dalo) Beetle
Dalo is one of the most important staple food crops in Fiji not only because of its traditional significance but also because of its economic importance. Fiji is currently the major exporter of dalo in the Pacific with exports valued at almost FJD25 million annually. However, Fiji’s dalo is also threatened by the dalo beetle, scientifically known as Papuana uniondis. Adult dalo beetle damage the underground corms by chewing and burrowing into them hence making large tunnels. Secondary rots develop resulting in low quality corms for sale and consumption. Dalo damaged by beetles cannot be exported.
Distribution
Dalo beetle was first found in Fiji in 1984 and since then it is localized in the Central Division of Viti Levu extending from Tailevu to Sigatoka and up to Vunidawa in the interior. Lovoni in Ovalau and the Ra Province from Nalidi to Navitilevu along the Kings Highway are also taro beetle infected areas. The presence or absence of dalo beetle in Bua, Cakaudrove in Vanua Levu is yet to be ascertained.
Life Cycle
The adult beetle is black, shiny, and 15-20 mm in length. Many P. uninodis species have a horn on the head with an average life cycle of 22 to 25 weeks. The adult beetles fly from the breeding sites to the taro field and tunnel through the soil and into the base of the taro corm. They then proceed to feed on the growing corm, leaving large holes that degrade the market quality and value of the corm. The wounds created while feeding promotes a path way for rot-causing organisms. The feeding activity can cause wilting and even death of the affected taro plants.
Control measures
Numerous efforts have been made to develop effective control measures for the taro/dalo beetle. These include:
Cultural control:
Crop rotation, clean planting material (free from soil, grubs and beetles)
Destruction of breeding sites (parameters around dalo gardens)
Chemical control: The chemical imidachloprid (Confidor) and permethrin (Mustang) have controlled Papuana beetles in Fiji. Please do seek advice from the Extension and Research Division of the Ministry of Agriculture (MOA) before using any chemicals on your farm
Biosecurity Containment, Advice and Control Measures
Avoid the movement of dalo corms, planting material and other dalo beetle host plants from dalo beetle infected areas to non-infected areas Contact your nearest Biosecurity Office for the necessary supervision of treatments to be carried out for infected taro planting materials Notify the nearest Biosecurity office or MOA office if you want to move dalo or dalo planting materials and are not sure of the dalo beetle infected areas
Fruit Flies
Fruit flies are a major concern for biosecurity as they cause damage to fruits and vegetables thus hinder production and decrease exports. Fiji has seven species of fruit flies which include Bactrocera passiflorae, light form of B. passiflorae, B. xanthodes, B. distincta, B. gnetum, B. kirki, and B. obscura. Two of these species – B. kirki and B. obscura are only present on the island of Rotuma and therefore Rotuma is a declared Biosecurity Emergency area for these two species.
Life Cycle
The adult female lays its eggs by making a puncture on the fruit using a needle like structure at the end of the abdomen and at the same time allows introduction of bacteria into the fruit. In about two days, the egg hatches and the larvae remain in the fruit during the larvae stage. The bacteria break down the fruit, providing food for the larvae or maggots that hatch from the eggs. Fruit damage caused by the fruit fly larvae becomes obvious after 3 days. The fruit tissue breaks down and brown black spot emerges on the fruit surface. In 5 to 7 days, symptoms of fruit fly damage are obvious through the rotting of the fruit. The rotten fruits fall to the ground, the larvae exit the fruit and pupate in the soil, emerging as adult flies. The entire life cycle of the fruit flies takes 18 to 20 days.
Biosecurity Trapping and Surveillance
The use of modified steiner fruit fly traps with three types of pheromones: Methyl eugenol, Cue lure & Trimed lure, serves as an early detection warning system. BAF in collaboration with the MOA Extension Division set up traps at all ports of entry (airports and wharves) and other high risk areas where exotic (foreign) fruit fly species are most likely to be detected if they come into the country. These traps are cleared routinely and the specimens are identified and recorded.
Biosecurity Concern
The two economically important fruit flies B. kirki and B. obscura which are present only in Rotuma pose significant threat to mainland Fiji’s fruits and vegetables and their export. Hence BAF would like to advice the travelling public to and from Rotuma that it is prohibited to bring any fruits from Rotuma into mainland Fiji. People found in breach of this biosecurity regulation are liable for prosecution and penalties.
Asian Subterranean Termites (AST)
In late 2009 and early 2010, Fiji saw an outbreak of AST in Lautoka and Labasa. AST, scientifically known as Coptotermes gestroi, is a new species of termite found in the country. It is exotic to Fiji and feed voraciously on timber and other wooden products. Because of this feeding habit, AST has caused massive damages to houses, schools and vegetation amounting to millions of dollars. AST is the second most destructive subterranean termite in the world.
Life Cycle
AST build their nests underground. They socially organize themselves into three groups which include reproductives, soldiers and workers. The ‘reproductives’ lay the eggs. Most colonies have one pair of primary reproductives; the king and the queen. A queen can live for about 20 years and lay 1,000 eggs a day. A colony can have about 60,000 to 1 million termites in it. Only the king and queen have eyes. The rest of the termites are blind and navigate using scent and moisture trails. Kings and queens are usually darker than the rest of the termites in the colony. The ‘soldiers’ are tasked to defend the nest from invaders, usually ants and termites from other colonies. The wide range of jaw types and large heads provide means that effectively block narrow termite tunnels against ant entry. A tunnel-blocking soldier can rebuff attacks from many ants. Soldiers’ heads are often darker than their bodies. They can exude a white toxic fluid for defence purposes. They also produce a rattling sound, a mechanism used by soldiers to warn off nest-mates by banging their head against the walls. The ‘workers’ are milky or cream in colour. They have smaller, saw-toothed mandibles, which allow them to take small bites of wood and carry building materials. As their name suggests they do most of the work in the colony. They dig tunnels, gather food and care for young. They also feed the king, queen and soldiers, who are unable to feed themselves. Workers and soldiers are sterile.
Biosecurity Concern
If AST spread into new areas, massive damage to infrastructure and vegetation will result. Lautoka and Labasa have been declared biosecurity emergency areas. The Biosecurity Emergency Declaration prohibits removal of any wooden materials, plants and plant products, timber and building material, furniture, personal effects and soil from infested areas. Offences carry penalties which can result in fines or imprisonment. Giant Invasive IguanasPests not Pets! The Giant Invasive Iguana (GII), commonly called the American iguana (scientifically known as Iguana iguana) is a declared pest in Fiji. It is said to have been brought illegally into the country and released on Qamea Island. Now almost 10 years later, GII have spread to Laucala, Taveuni and Matagi Island as well. If the GII are not controlled and eradicated, it could have disastrous effect on our environment, biodiversity, food security and economy.
About GII
GII are native to Central and South America. It has not only been declared a pest in Fiji but in other countries as well because of the damages it has caused to the environment and biodiversity of these countries. Adult GII can grow to almost two meters in length and nine kilograms in weight. They also have long flaps of saggy skin hanging from the chins to the base of their necks, which is called a dewlap. On both sides of their cheeks, they have a large scale underneath their tympanums (a slightly sunken leathery covering of their eardrums). The dewlap and large scale are ways to identify and differentiate GII and the Fiji iguanas. GII breed rapidly and a female can lay 50 to 80 eggs. As herbivores, GII mainly eat plants. They have very sharp teeth and can shred leaves and branches with great ease. They are also very good swimmers. When threatened, GII will dive into the water from their tree perch and swim away swiftly.
GII are a threat and need to be controlled and eradicated.
GII pose immediate threat to food security in villages and islands where they are present as they eat plants such as dalo, cassava, bele, tomatoes, cabbages, beans and yams. If GII numbers are left unchecked, food sustainability in Fijian villages will be at great risk in the near future. Large numbers of GII would devastate the environment around the villages and cause unpredictable economic hardship.
What’s being done to eradicate the GII from Fiji
A GII Eradication Campaign Taskforce is in place to eradicate these iguanas. The taskforce carries out community outreach programmes highlighting the potential harm GII have brought to Fiji’s endemic iguanas, tourism industry, village vegetable gardens and the thriving agricultural industry. The eradication of these iguanas is a challenge as they are arboreal (tree dwelling), well camouflaged and have excellent eyesight, thus, able to avoid detection. They are also excellent swimmers and usually climb a tree and drop into water where they can stay submerged for an hour or more. A good way of eradication would be locating all GII nestling areas and controlling the breeding by destroying the eggs.
Biosecurity Concern
Apart from agriculture, environment and tourism (economic) concern, GII could affect Fiji’s biodiversity having a serious impact on endemic plants and bird eggs and nestlings. GII also pose risk to our endangered native iguanas through the possible transmission of iguana- specific diseases, parasites and pathogens. Any person found in possession of or transporting this pest will incur heavy penalties. People should report any sightings of the GII to BAF. Please assist BAF contain these pests in their current areas of distribution by not moving them and their host materials. Seek BAF advice and approval before moving any materials that may help the above pests get to new areas in Fiji.