Jaw-dropping Facts About Japanese Beetles — Animal Sake

Jaw-dropping Facts About Japanese Beetles

Japanese beetles are gorgeous looking beetles, however, they are very nasty and conduce to widespread destruction. They devour leaves, flowers, fruits of trees and also strip lawns and golf courses off their beautiful grass.

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Japanese beetles are gorgeous looking beetles, however, they are very nasty and conduce to widespread destruction. They devour leaves, flowers, fruits of trees and also strip lawns and golf courses off their beautiful grass.

Appearance of Japanese Beetle

Japanese beetles (Popillia japonica) are 1/2 inch in size, with metallic green body. They have copper-colored wings and white hair tufts under the wing covers on each side of the body, which is a differentiating feature. They are round, oval shaped insects with brownish-orange fore wings. About 1.3 cm long, these beetles have a ringed abdomen and antennae clubbed at the end. The false Japanese beetle, Bumble Flower Beetle, scarab beetles in the genus Anomala are mistaken as Japanese beetles.

Leaf-eating Japanese Beetle

Attractive looking Japanese beetles wipe out foliage in gardens, which is why they are a gardener’s enemy. They eat away leaf tissues, leaving only the veins of leaves behind. They chew entire flower petals and leaves and can strip a fruit tree of its leaves in flat 15 minutes. Grubs (baby beetles) feed on grass roots, which debilitates the ability of grass to draw enough water from the soil to survive the heat.

Japanese Beetle Reproduction

Japanese beetles enjoy warm weather and come out of the soil when the sun is out, for eating and mating. They are active from mid-June to mid-September; most active during the hottest part of the day. After mating, by late afternoon, the female burrows her way into the soil (2-4 inches) for laying her eggs. She lays 1-5 eggs every 2-3 days and has the capacity to lay about 60 eggs during her lifespan.

Lifespan of Japanese Beetles

The eggs hatch in 2 weeks and the beetle grubs start chewing on grass roots. When the temperature drops in late September, the grubs burrow deeper in the soil and hibernate for the next 10 months. They emerge in late May and feed on the roots of turf grasses and vegetable seedlings. By mid-June, they pupate into adults and undergo a full swing feeding and mating activity for the next 4-6 weeks, after which they die off. The average lifespan of an adult Japanese beetle is only 30-45 days.

Feed in Groups

While devouring a plant, the Japanese beetle secretes ‘congregation pheromone’ that attracts other Japanese beetles to come to the same area and enjoy the feast. Japanese beetles usually feed in groups and consume the upper portion of plants and trees before moving down to the rest. Japanese beetle grubs are America’s number 1 turf pests, as they devour the roots of grass, thereby damaging turf.

Japanese Origin of Pest

Native to Japan, these beetles were accidentally introduced to New Jersey (USA) in 1916, via imported iris bulbs. Eastern United States is infested by this pest, as the climate there proves to be suitable for its growth. They devour lawns, gardens and golf courses here. Ironically, Japanese beetles are not such a problem in Japan, where natural predators (parasitic wasps), cooler temperatures and absence of proper larval habitat curtails their numbers.

Soap Water to kill Japanese Beetles

After the sun is up, shake the trees in garden and let the beetles fall in a tub of soap water. Soap water will drown and kill these beetles. Repeat it again in the afternoon. Capable of flying about 8 km with the wind, however, most of the time they fly short distances. So, remember to wear headgear as they can fly in to your face.

Traps for Japanese Beetles

One trap uses female beetle pheromones to attract the beetles, while the other uses luring aroma of food to trap the beetles. Place them away from the plants. However, you need to keep an eye on these traps because at times these traps lure more beetles than their killing capacity.

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Beetle Bug 3

The world’s most famous Irish Beetle Bug is back! Help rescue over one thousand of his insect children that were kidnapped on a trip to the grocery store.

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Description

The world’s most famous Irish Beetle Bug is back! Help rescue over one thousand of his insect children that were kidnapped on a trip to the grocery store. Beetle Bug 3, the third chapter of the Beetle Bug series features all new enemies and a ton of new extras and puzzles.

Beetle Bug 3 Features

  • Out of the box storyline with crazy characters;
  • Classic gameplay totally overhauled;
  • One hundred levels featuring 25 objects, different weapons and monsters;
  • Use mouse or keyboard controls alternatively;

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Requirements

  • File Size: 38 Mb
  • Windows 98/XP/Vista/7/8/10

Licensing terms and policy

All full version games provided at this web-site were licensed, sublicensed for distribution by other game developers, game publishers or developed by internal game studio and provided free legally. If you have questions about this game, please contact us using this form.

www.gametop.com

Volkswagen ID.3 to be as important as the Beetle

The Beetle was one of the world’s most important cars, and now Volkswagen believes its newest vehicle will have the same global impact.

Volkswagen is ending production of the last version of its Beetle model (CBS)

The much-loved vehicle has been part of our lives for eight decades — sold and instantly recognisable around the world.

Volkswagen has unleashed a car it hopes will be as influential as the original Beetle that put so many families on wheels.

The ID.3 hatchback is about the size of a Volkswagen Golf but eschews a petrol engine for electric motors, the first of many planned electric models from the German car making giant.

It is built on a new electric architecture that will form the basis of a multi-billion dollar push into the emerging electric vehicle space.

The Volkswagen ID.3 electric car is the brand’s third major chapter after the Beetle and Golf. Source:Supplied

“The ID.3 marks the start of a major e-mobility campaign for the Volkswagen brand,” says Volkswagen Group CEO Herbert Diess.

“In around ten years almost half of the Group’s cars in Europe and China will be electric. No other established manufacturer is pursuing this course as rigorously as we are.”

Volkswagen referred to the ID.3 as the “third major chapter” in its 82-year history, behind the Beetle and Golf.

The Volkswagen ID.3 won’t arrive in Australia until at 2022 at the earliest. Source:Supplied

Partly borne from the desire to clean its image after the Dieselgate scandal whereby the brand was caught cheating its emissions on diesel vehicles, the ID.3 is the first of a family of all-electric ID models that will include a modern remake of the legendary Kombi.

“The ID.3 is an all-rounder that is suitable for everyday use,” says Silke Bagschik, head of sales and marketing for a planned ID family. “It is compact, as such offering the manoeuvrability of a small car with the interior space of a mid-range vehicle.”

The Volkswagen ID.3 is the first EV of a planned family of vehicles. Source:Supplied

Volkswagen will initially offer three ID.3 models, each stepping up its battery capacity to deliver a longer driving range between charges.

The basic car has a 45kWh battery capable of 330km whereas the top-of-the-line gets a 77kWh battery claimed to travel 550km between charges.

Unveiled ahead of this week’s Frankfurt motor show, the ID.3 will be priced from less than €30,000 in Europe, or a bit more than $48,000.

However, it won’t arrive in Australia until 2022 at the earliest.

The Volkswagen ID.3 costs about $50,000. Source:Supplied

While car makers as diverse as Tesla, Nissan and BMW have been producing electric vehicles for years, Volkswagen calls the ID.3 “pioneering” and a “new, electric way of thinking”.

In revealing the ID.3 Volkswagen also updated its logo, the first major change since 2000.

It uses a simplified version of the VW lettering inside a dark blue circle.

Chief marketing officer Jochen Sengpiehl says it is about positioning the brand as “more human and more lively, to adopt the customer’s perspective to a greater extent and to tell authentic stories”.

www.news.com.au

Automobile History — Top 10 Interesting Facts

Automobiles have been around since as early as 1769, when the first steam engine powered automobiles were produced. In 1807, Francois Isaac de Rivaz designed the first car that was powered by an internal combustion engine running on fuel gas. The journey of modern automobiles began in 1886 when German inventor Karl Benz created an automobile that featured wire wheels with a four-stroke engine fitted between the rear wheels. Named as ‘Benz Patent Motorwagen’, it was the first automobile that generated its own power, which is the reason why Karl Benz was given its patent and is called the inventor of modern automobiles.

So we shortlisted ten things you probably did not know about the history of automobiles.

1. Adolf Hitler ordered Ferdinand Porsche to manufacture a Volkswagen, which literally means ‘People’s Car’ in German. This car went on to become the Volkswagen Beetle.

What’s also interesting to know is that a surviving sketch from the 1930s — that was allegedly penciled by Hitler himself — looks similar to the production version of the first Beetle. The drawing was said to have been given to Daimler-Benz before being given to Porsche in Nuremberg.

See also:  6 Effective Treatments to Get Bed Bugs out of Your Car, Dengarden

2. In 1971, the cabinet of Prime Minister Indira Gandhi proposed the production of a ‘People’s Car’ for India — the contract of which was given to Sanjay Gandhi. Before contacting Suzuki, Sanjay Gandhi held talks with Volkswagen AG for a possible joint venture, encompassing transfer of technology and joint production of the Indian version of the ‘People’s car’, that would also mirror Volkswagen’s global success with the Beetle.

However, it was Suzuki that won the final contract since it was quicker in providing a feasible design. The resulting car was based on Suzuki’s Model 796 and went on to rewrite automotive history in India as the Maruti 800.

3. Rolls-Royce Ltd. was essentially a car and airplane engine making company, established in 1906 by Charles Stewart Rolls and Frederick Henry Royce.

The same year, Rolls-Royce rolled out its first car, the Silver Ghost. In 1907, the car set a record for traversing 24,000 kilometers during the Scottish reliability trials.

4. The most expensive car ever sold at a public auction was a 1954 Mercedes-Benz W196R Formula 1 race car, which went for a staggering $30 million at Bonhams in July 2013. The record was previously held by a 1957 Ferrari Testa Rossa Prototype, sold in California at an auction for $16.4 million.

5. As a young man, Henry Ford used to repair watches for his friends and family using tools he made himself. He used a corset stay as tweezers and a filed shingle nail as a screwdriver.

6. In the year 1916, 55 per cent of the cars in the world were Model T Ford, which is still an unbroken record.

7. Volkswagen named several of its cars after wind. Passat — a German word for trade wind; Golf — Gulf stream; Polo — polar winds; Jetta — jet stream.

8. British luxury car marque Aston Martin’s name came from one of the founders Lionel Martin who used to race at Aston Hill near Aston Clinton.

The company was owned by Ford Motor Company from 1994 till 2007. However, Ford still owns stakes in the company.

9. The first road-worthy cars used a lever instead of a steering wheel to steer. It had a design and functioning like that of a joy stick.

10. Jamaican reggae singer-songwriter and guitarist, Bob Marley owned a BMW, not for prestige but because of the coincidence of initials for Bob Marley and the Wailers.

For the latest auto news and reviews, follow CarandBike on Twitter, Facebook, and subscribe to our YouTube channel.

www.carandbike.com

VOLKSWAGEN ATLAS NAMED 2018 BEST THREE-ROW SUV FOR FAMILIES BY PARENTS MAGAZINE AND EDMUNDS

Jun 5, 2018

Volkswagen’s midsize SUV praised for spaciousness, driving dynamics and the People First Warranty

Herndon, VA (June 5, 2018) — Volkswagen of America, Inc. is proud to announce that the 2018 Volkswagen Atlas has been named Best Three-Row SUV in the 10 Best Family Cars for 2018 list by Parents magazine and Edmunds.

“We are so proud to be named one of the 10 best cars for families by Parents magazine and Edmunds,” said Derrick Hatami, Executive Vice President of Sales and Marketing for Volkswagen of America, Inc. “The 2018 Atlas was designed and assembled in America specifically with American families in mind. Three rows of highly configurable seating with the latest tech features and Volkswagen’s trademark style and driving dynamics is definitely a winning combination.”

Editors at Parents magazine praised the Atlas for third-row legroom, the six-year or 72,000 mile warranty and ease of maneuverability. “We rated the steering 5 out of 5,” said Dan Edmunds, head of vehicle testing at Edmunds (but no relation). “It drives a lot smaller than it is.”

To compile the annual list, Parents and Edmunds first looked at safety ratings, narrowing contenders to the 109 that were a Top Safety Pick by the Insurance Institute for Highway Safety or received a 5/5 star overall rating from the National Highway Traffic & Safety Administration. Edmunds rated the mechanics of each of those vehicles, and Parents installed car seats and looked for family-friendly features in 20 finalists.

The 2018 Volkswagen Atlas was introduced in Spring 2017 as the brand’s first three-row SUV. Designed specifically for the American family, the 2018 Atlas is available with two engine options—a 2.0-liter, turbocharged four-cylinder and a 3.6-liter V6—and in five trim levels: S, SE, SE w/ Technology, SEL, and SEL Premium. Atlas also offers 4Motion® all-wheel drive on a variety of trims and is assembled in Volkswagen’s state-of-the-art plant in Chattanooga, Tenn. Manufacturer’s Suggested Retail Prices start at $30,750.

Atlas, along with the rest of the 2018 Volkswagen family (excluding e-Golf), comes with the People First Warranty, a six-year or 72,000-mile (whichever occurs first) bumper-to-bumper New Vehicle Limited Warranty, which includes powertrain coverage for engines, transmissions and optional 4Motion® all-wheel-drive systems and can be transferred to subsequent owners throughout the remainder of its duration.

For more information about the 10 Best Family Cars for 2018 list by Parents magazine and Edmunds, please visit Parents.com/BestCars.

About Volkswagen of America, Inc.
Founded in 1955, Volkswagen of America, Inc., an operating unit of Volkswagen Group of America, Inc. (VWoA) is headquartered in Herndon, Virginia. It is a subsidiary of Volkswagen AG, headquartered in Wolfsburg, Germany. VWoA’s operations in the United States include research and development, parts and vehicle processing, parts distribution centers, sales, marketing and service offices, financial service centers, and its state -of-the- art manufacturing facility in Chattanooga, Tennessee. The Volkswagen Group is one of the world’s largest producers of passenger cars and Europe’s largest automaker. VWoA sells the Atlas, Beetle, Beetle Convertible, e-Golf, Golf, Golf Alltrack, Golf GTI, Golf R, Golf SportWagen, Jetta, Passat, Tiguan, and Tiguan Limited vehicles through more than 650 independent U.S. dealers. Visit Volkswagen of America online at www.vw.com or media.vw.com to learn more.

Notes:
This press release and images of the 2018 Atlas are available at media.vw.com. Follow us @VWNews

“4Motion”, “VW”, “Volkswagen”, all model names and the Volkswagen logo are registered trademarks of Volkswagen AG.

Features and technical data apply to models offered in the USA. They may differ in other countries.

The 2018 Atlas earned a 5-star overall rating from the National Highway Traffic Safety Administration (NHTSA). Government 5-Star Safety Ratings are part of NHTSA’s New Car Assessment Program (www.safercar.gov).

The Manufacturer’s Suggested Retail Price (MSRP) excludes transportation, taxes, title, options, and dealer charges. Dealers set actual prices.

6 years/72,000 miles (whichever occurs first) New Vehicle Limited Warranty on MY2018 VW vehicles, excluding e-Golf. Based on manufacturers’ published data on transferable Bumper-to-bumper/Basic warranty only. Not based on other separate warranties. See owner’s literature or dealer for warranty exclusions and limitations.

www.media.vw.com

Four-lane leptur: basic information about the beetle family beetle

Cars of the 1940s and 1950s around the world were big and trimmed to the gills in chrome. While most looked like airplanes and were stunning to look at, they also cost a small fortune to run. Enter the Volkswagen Beetle. First introduced in 1938, the tiny ‘people’s car’ shot to prominence after World War II. It was basic, still managed to fit the family, and ran on the smell of an oily rag. It went on to sell nearly 22 million units over its lifetime.

In 2016, this iconic car drove off into the sunset for the last time. After slow sales, the Beetle is no more in Australia, and the German auto giant marked this occasion with a special limited-edition car, the Beetle Classic. It’s back-to-basics, with no options, taking inspiration from the original Bug. So, to see just how much has changed over the decades, we put it up against my very own 1965 VW Beetle.

The old Beetle was $1700 new and powering it was a 1200cc engine (my car has been upgraded to 1600cc) which pushed out a minuscule 22kW of power and 70Nm of torque. The engine is located in the rear and relies on air to cool it, so no need for a radiator.

Safety wasn’t really a top priority in 1965 either, as the car didn’t come with rear seatbelts, airbags or any of the clever safety features of today. Even a radio was an option.

Everywhere you look, there’s chrome. The bumpers, side body trim, mirrors, headlight surrounds, hubcaps, door handles – the list goes on. And you can’t beat that unmistakable bonnet which resembles the wings of the very insect its name derives from.

There’s only room for a few bags of groceries under the bonnet (sounds weird, huh?), as the spare wheel and fuel tank takes up the majority of the room. Although, a suitcase can fit behind the back seat.

The vinyl low-back seats are springy and you almost rub shoulders with your front seat passenger. In the back, it’s a tight fit for any adult, but would be fine for children.

So, how does it drive? Slow. Any speed over 90km/h, the engine starts to whine and it becomes loud. Although, it’s happy to putt around town at low speed. It’s a reminder that the Beetle was never famous for its power. There is no power steering, as most of the weight is on the back wheels, so the wheel is very light to turn.

The four-speed gearbox is synchronised and reverse is found by pressing down on the gear knob. The first gear ratio is that close, that taking off in second gear is recommended. Back then, the close gear ratios were good for towing, but with drum brakes all-round, it’s probably not a great idea.

Now, over to the Beetle Classic.

It will set you back $36,990 plus on-roads, but with only 53 of them made, it has the potential to be a future collectable. The number 53 isn’t because of the world-famous racing Bug, Herbie, but denotes the year the Beetle was first imported to Australia. What makes it even more special is, that this specific car is number 53 – the last Beetle in the country, ever.

This more ‘tougher’ design replaced the somewhat ‘girly’ look of the New Beetle from the early 2000s (flower on the dashboard, anyone?), and this latest iteration really gets close to the look of the original Beetle. Other noticeable similarities are the chrome hubcaps and dress rings, chrome side mirrors, side body trim and even the Volkswagen logo on the boot.

The biggest difference to the old model is the engine is situated in the front and has a radiator. And it’s more powerful, with a turbocharged and supercharged 1.4-litre engine, producing 118kW of power and 240Nm of torque.

The Beetle Classic is by far a much safer car, with ABS, blind-spot monitoring and a rear-view camera. And not to mention, disc brakes, so stopping is a much more pleasant experience.

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Boot space is at 310 litres, and increases to 905 with the two-seater back seats folded down. It was tested with boxes of kitchenware and even a front beam of an old Beetle wrapped in sheets, and had no problem accommodating them.

After pressing down on the Start/Stop button for a couple of seconds, the car fires up, but it doesn’t have that iconic ‘dak-dak’ noise.

It isn’t super-fast, but it does take off from a stand-still quite quickly. Engaging sport mode feels like the car turns into Herbie. It kicks your head back and revs hard, to the point where you need to return to Normal driving mode or use the paddle-shifters for it to change down a gear.

The petrol engine is teamed with a seven-speed DSG automatic transmission, which is clunky crawling through peak-hour traffic, but going through each gear is smooth as silk.

After driving these cars back-to-back, it’s clear to see how the cute little Bug can niggle its way into your heart. The 1965 Beetle is charming and whoever crosses its path, they’re sure to smile. The Beetle Classic is the closest you will get to the Beetle of old, while still having the added assurance of safety features.

To one of the cutest cars in the world, Australia says thanks for the memories.

Click on the Photos tab for more images by Tom Fraser.

www.caradvice.com.au

l. INTRODUCTION AND GENERAL INFORMATION

Insects and mites are often found infesting cured fish during and after processing, especially in the tropics and subtropics. The purpose of this field guide is to provide basic information on the appearance and ecology of the main types of insects and mites that cause losses to cured fish.

1.1 Importance of insects and mites on cured fish

Cured fish can suffer considerable loss of weight due to feeding damage by insect and mite pests. Under adverse conditions, quantitative losses of up to 30% due to fly damage during processing, and up to 50% due to beetle damage during storage for several months, have been reported. Under better conditions of processing and storage, the weight losses due to pest infestation are often much less than these extreme values, but they usually represent a significant wastage that could be reduced by prevention and control of pest attack. Published and unpublished reports of losses due to insect damage on cured fish have been summarized and discussed by FAO (1981).

Pest damage can also cause fragmentation of the cured fish (FAO, 1981), which Can lead to quantitative loss of the smaller fragments (or downgrading of this fraction for use as animal feed) and loss of value due to quality reduction, since a higher price is often obtained for intact pieces of fish. Contamination by live or dead pests, or by their cast skins and frass (excreta), also causes a change in visual quality that may reduce the value of the fish. Additionally, insect and mite pests often transmit mould spores, and the heat and moisture produced by heavy infestations can create conditions suitable for mould growth on fish that has previously been dried.

1.2 Life-cycle and development of insects and mites

During development from egg to adult, insects and mites pass through several distinct stages. At the end of each stage, the old skin or cuticle (which forms a thin external skeleton) is shed and the next stage emerges with a fresh cuticle, which is initially elastic and thus allows growth before it hardens

In many insects, including the beetles and flies found on cured fish, the immature stages are completely different in appearance from the adults; this type of life-cycle is called complete metamorphosis. In such insects, the egg hatches to produce a larva, which may have three pairs of jointed legs (e.g., most beetle larvae) or none (e.g., fly larvae). The larva is predominantly concerned with feeding and growth, and passes through several stages (instars) and moults before reaching full size. The last larval instar then changes into a legless pupa, which has no mouth. During the pupal stage, the body of the insect is reorganized into the adult form. This reorganization may be visible in pupae that have thin cuticles (e.g., beetle pupae) but hidden in others (e.g., those fly pupae in which the last larval cuticle is retained and becomes thickened as a puparium enclosing the pupa). Finally, the pupa moults to release the six-legged adult, which usually has one or two pairs of wings. The adult may feed on the same food as the larva or on a different food, or it may be short-lived and not feed at all; whether or not it feeds, the primary purpose of .the adult stage is to reproduce and lay eggs. Detailed information on the structure and development of insects is given by Richards and Davies (1977, 1977 a).

In all mites and some insects, the immature stages are very similar to the adults in appearance, and also in their feeding habits and general behaviour; this type of life-cycle is called incomplete metamorphosis. In mites, the egg hatches into a six-legged larva, which then moults to produce a nymph with the eight legs that typify mites and other arachnids. Development then proceeds through one, two or three nymphal instars. The nymphs usually closely resemble the adult form, differing mainly in their smaller size and lack of external genital openings. In the species of mites commonly found on cured fish, there are two such normal nymphal stages, the protonymph and tritonymph. However, between these two normal stages a special type of deutonymph may occur -a hypopus, which has reduced mouth parts and does not feed, but which has a number of suckers that allow it to cling to insects for dispersal. The last nymphal stage moults directly to the adult, which feeds in the same way as the normal nymphs but has fully-developed genitalia for reproduction. Further information on the development and biology of mites is given by Hughes (1976) and Krantz (1978).

1.3 General ecology of insects and mites

Once an infestation of an insect or mite pest becomes established, its population tends to increase exponentially: i.e., the total numbers follow a geometric series over equal time intervals. Under ideal conditions for the particular pest species, the rate of increase may be very high. For example, in the common beetle pests of cured fish, the optimum rate of increase is 25-30 times in 4 weeks (Howe, 1965); i.e., at optimum conditions, one fertile female could give rise to 15 625-27 000 beetles in 12 weeks. Mite pests have even higher rates of population growth, with optimum rates of increase reaching many hundreds of times per month. If fish processing and storage conditions favour rapid development of pests it is essential that infestations are detected and controlled at an early stage, before large populations cause unacceptable levels of damage.

The actual rates of increase occurring in practice are, however, affected by many environmental factors. The more important of these factors are temperature, moisture, and the nature of the food (physical form and nutritional quality).

Insect and mite development can only occur within certain ranges of temperature, dependent on the species. Within its range, each pest species has an optimum temperature, usually less than 5°C below its maximum temperature limit, at which its rate of increase reaches a peak. Typically, for pests of cured fish this optimum temperature is somewhere between 25° and 35°C. If exposed to temperature in excess of their maximum, insects and mites are eventually killed, unless they can disperse to cooler conditions. Below their optimum temperature, their rate of increase is progressively reduced until, at their minimum temperature limit, development ceases.

The development of insect and mite pests is similarly affected by moisture content and relative humidity. In particular, low moisture levels are an important limiting factor for most pests of cured fish and other dried food. The flies that infest moist partially-cured fish are especially susceptible to lack of moisture and usually cannot develop on the fully-cured product. Most of the other pests have high rates of increase on cured fish with moisture contents in equilibrium with 70-80% r.h. As the equilibrium r.h. is reduced below 70%, the rates of increase of these pests (especially the flies and mites) are considerably reduced, and well-dried fish is much less susceptible to damage by most pests.

The physical nature of cured fish, especially the extent of any fragmentation, affects the availability of the flesh, and thus the rate of increase of pests feeding on it. This is likely to be especially true for mites. Different genera of cured fish have been found to vary in their susceptibility to infestation by beetles and mites, though the nutritional factors governing this variation have not been identified. The presence of the salt on salted cured fish reduces the rates of increase of most insects and mites, though the pest species vary in their response to different concentrations.

Further information on the effects of temperature, moisture and food type on pests of cured fish is given by FAO (1981).

1.4 Collection and examination of insects and mites

The main groups of pests of cured fish can usually be recognized with the naked eye or, preferably, by the use of a simple hand-lens, while they are still on the fish sample. However, if confirmation or more detailed identification is required, or if insects or mites other than the main pest types seem to. be present, specimens should be collected for examination in the office or laboratory.

The simplest procedure, which reduces the amount of work in the field and also ensures that species are not over-looked, is to take samples of the infested fish, together with the pests, and place them in polythene bags (or similar sealed containers). The samples can then be examined in detail on a tray in the office or laboratory, and the pests extracted carefully. Collection of such samples may be essential if only the larvae or pupae of flies or beetles are present on the fish, and if detailed identification is required. Such specimens should be kept alive on the sample (in jars cloyed by pieces of cloth secured with rubber bands) until the immatures develop into adults, which are easier to identify.

Active adults of flies and beetles are usually easier to catch by using an entomologist’s net, and transferring them to small tubes or jars. A suitable «butterfly» net can be purchased from biological equipment suppliers, or it can be made locally by stitching soft mosquito-netting into the shape of a bag and fitting this onto a circular, ovate or triangular frame of metal or bamboo with a light wooden handle. This method is particularly useful for sampling pests that are flying around fish processing sites.

See also:  Plum pests and how to deal with them, by garden expert Helen Yemm, The Telegraph

Insects and mites infesting flaked fish can be separated by sieving; the sieve aperture-size required will be governed by the average size of the fish flakes in relation to the size of the particular pests present.

In order to collect insect specimens from relatively intact fish pieces in the field, or to remove them from fish samples in the office or laboratory, one should use either lightweight forceps (preferably soft ones to reduce the likelihood of damaging the specimens) or a small aspirator. Mites can also be collected with an aspirator. It is possible to use a moistened fine artist’s brush to collect small insects and mites, but this requires some practice.

The specimens should be placed in small labelled tubes (25 x 50 mm, or smaller,). Most specimens will not be damaged by being kept in such tubes for up to 24 h but, if it is necessary to keep them for longer, preservative fluid should be added to the tube before sealing it, as described in section 1.5, below: this will kill the specimens and prevent their deterioration.

Samples or specimens should always be labelled, and notes made, at the time of collection in the field. The label attached to, or placed in, the sample bag or tube should give the most essential collection data (i.e., the location, type of cured fish, and date) in abbreviated form, together with a sample number. The full collection data, including notes on precise collection details, quality of fish, level of infestation, etc., should then be entered against the sample number in a notebook. It is not advisable to write only the sample number on the label, because field notebooks are sometimes lost or mislaid.

If a label is to be placed inside a sample tube containing preservative fluid, it must be written clearly with a pencil or with permanent black drawing ink; most other inks, whether water- or spirit-based, are dissolved by preservative fluids, and this includes the inks used in ballpoint pens. Further information on collecting and labelling of pest specimens is given by Oldroyd (1970), British Museum (Natural History) (1974), Hodges (1980) and Dobie et al (1984).

In order to confirm, in the office or laboratory, to which main pest group a specimen belongs, a simple hand-lens or bench-lens may be necessary. In order to identify pests more precisely by using identification keys such as those given by Freeman (1980), Dobie et al. (1984) and Halstead (1986) , it is usually essential to use a microscope. A cheap low-power «dissecting» microscope is normally sufficient. Identification of mites, however, by using keys such as those given by Hughes (1976), requires specialist knowledge and a high-power transmitted-light microscope.

1.5 Preservation of specimens

If insect and mite specimens are to be retained for further identification, or as reference specimens, or for any other reason, they must be preserved. If the specimens have already been placed in preservative at the time of collection, it is still usually advisable to transfer them to fresh preservative (and to remove any fish flakes or other debris). Adult flies (and other insects) are commonly preserved dry on entomological pins or stuck to card with a water-soluble glue (British Museum (Natural History), 1974). This technique is, however, unsuitable for long-term storage in warm humid climates, where the specimens may be destroyed by mould, and in many climates the dried insects are susceptible to attack by museum beetles and similar scavengers. It is therefore generally preferable to keep most insect and mite pests of cured fish in preservative fluid (as described below) in small labelled tubes. The main exception is that, if adult flies are to be sent to a museum or a specialist for identification, they should be dried and then packed gently in a small box between layers of tissue, as they lose their colour in preservative.

The best general-purpose preservative is Pampel’s Fluid. This is prepared by mixing the following ingredients together (in parts by volume to give the quantity required) in the order shown: 30 parts water (preferably distilled); 15 parts 95% ethyl alcohol; 6 parts 40%(w/v) formaldehyde; and 4 parts glacial acetic acid. (Never start with the acid: always add it slowly after mixing the other ingredients.) If possible, let the mixture stand for a few days before use: the unpleasant smells of the acid and aldehyde will then have disappeared. If glacial acetic acid is not available, or is considered too dangerous to transport or stock, replace the water and concentrated acid in the above list with either 7.5 parts water and 26.5 parts 15% acetic acid solution. or 14 parts water and 20 parts 20% acetic acid solution. If industrial acetic acid is not available. A similar (but weaker) preservative can be made by mixing: 35 parts strong vinegar (preferably white); 15 parts absolute (> 99.5%) ethyl alcohol; and 2.5 parts 40%(w/v) formaldehyde.

An alternative preservative. which is particularly suitable for mites and insect larvae. is Oudeman’s Fluid. This is made by mixing together (as for Pampel’s Fluid): 87 parts 70% ethyl alcohol; 5 parts glycerol; and 8 parts glacial acetic acid. Because of the high proportion of acid to water in this fluid. it is only possible to make it withough glacial acetic acid by using 25% acid solution and concentrated alcohol: 63 parts 95% ethyl alcohol (or 61 parts absolute alcohol plus 2 parts water); 32 parts 25% acetic acid solution; and 5 parts glycerol.

If Pampel’s Fluid or Oudeman’s Fluid cannot be prepared. then 70% ethyl alcohol or 10% formaldehyde can be used though these both tend to harden specimens and the latter causes discoloration. In the absence of any of these preservatives. a colourless alcoholic liquor can be used. If available. but it should be noted that at normal strengths of only 40% alcohol this is not such an effective preservative.

As described earlier. the specimen tubes must be labelled and the labels must be written in pencil or black drawing ink. The tubes should be well-filled with preservative to cover and protect the specimens even when they are moved. A small wad of soft absorbent paper can be used to reduce the volume of preservative and restrict the movement of robust specimens. but care must be taken not to trap air-bubbles below the paper; this should not be done with delicate or small specimens (small insect larvae or mites) as they often become entangled in the fibres. The tube must be very well sealed to prevent evaporation or leakage of the preservative: cork stoppers should be sealed with melted wax. if possible, and rubber or plastic closures should be secured with adhesive tape.

If specimens are to be sent by post or courier to a specialist for identification. the tubes must be well protected from damage. A simple method using commonly available materials is to bore a hole in a small block of expanded polystyrene packing. push the specimen tube entirely into the hole. and pack the block in a small cardboard box or a padded bag. Other methods are described by British Museum (Natural History) (1974). Hodges (1980) and Dobie et al (1984).

1.6 Main types of insects and mites found on cured fish

The pests commonly found on cured fish are beetles (Coleoptera) or flies (Diptera). or mites (Acarina).

The adults of the beetles all have six legs. a large thoracic segment behind the head. and a pair of hard wing-cases (elytra) that cover much or all of the abdomen. These elytra are actually modified fore-wings; the hind-wings are normal but are usually completely hidden under the protective elytra. except in a few species which have no hind-wings. The larvae of the beetles normally have 3 pairs of jointed legs. one on each of the 3 segments behind the head. and sometimes have one or two horn-like protuberances at the end of the segmented abdomen. Some beetle larvae are covered densely with long hairs, but others are almost smooth. The main beetle pests of cured fish are Necrobia rufipes and Dermests species.: these are described in sections 2 and 3 of this guide. Other beetle adults are sometimes found on cured fish. The anobiid Lasioderma serricorne (Fabricius). which is small (2.0-2.5 mm) and reddish-brown with its head partly hidden below the thorax. is a pest of many dried commodities and has been reported from cured fish in South Asia. Various Species of predatoryhisterid beetles. especially species of Saprinus and its relatives. are occasionally found on cured fish. especially in association with infestations of Dermestes larvae on which they prey; these beetles are broadly oval almost hairless. black and shining (sometimes with metallic lustre or pale spots). and the elytra are rather shorter than the abdomen (Hinton. 1945 a).

The adults of the flies all have six legs. large eyes, and one pair of membranous wings. Behind and slightly below the base of each wing is a small club-like structure (haltere) that may be partly concealed by a protruding lobe; the paired halteres are gyroscopic balancing organs and are modifications of the hind-wings. Fly larvae. often called maggots. have no leg8. a very small head. and barely visible mouth parts formed mainly of two hook-like mandibles. The larvae are generally cylindrical. though often tapering towards the head. and sometimes have numerous protuberances. The pupae are protected by hardened puparia. which are cylindrical with rounded ends and vary in colour according to species and age. All flies associated with cured fish are in the advanced suborder Cyclorrhapha. and the majority belong to the family Calliphoridae (the blow-flies, blue bottles, green bottles, and flesh flies). The common types of fly found on cured fish are described in section 5 of this guide.

Mites are very small (always less than 1 mm and usually less than 0.5 mm) and their thin-skinned oval bodies are usually a translucent creamish-white. Because of their small size, mites are often not noticed; if cured fish has a dusty rough-textured appearance, the «dust» may in fact be mites. Mites never have wings, and the segmentation of the body that is clear in most insects is not visible in mites. The larvae have only six legs, but the nymphal stages and adults have eight legs. Most of the species of mites that are pests on stored foods belong to the family Acaridae. On cured fish, the commonest acarids are species of Lardoglyphus, which are described in section 4 of this guide: other types of acarid, or similar pest groups, are rarely found on this commodity. Predatory mites, which are usually distinguishable by their long legs and fast movement, may occasionally be seen, but only in small numbers. Accurate identification of mites requires specialist knowledge.

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