Blueback herring

Blueback herring

Alosa aestivalis (Mitchill, 1814)

Cool Facts

A The oldest age reported for blueback herring is 8 years. The heaviest reported weight for blueback herring is 200 g (0.44 lbs.)

SIZE: The common length for blueback herring is 27.5 cm (11 inches) with the maximum reported length being 40 cm (15.7 inches).

RANGE: The range of Blueback herring extends from the lower parts of Cape Breton rivers in Nova Scotia, Canada and south to the St. John’s River in Florida.

HABITAT: Blueback herring spawn in brackish water or fresh water rivers. Their eggs are essentially pelagic in still water. Blueback herring larvae are found in fresh and brackish rivers. Juvenile blueback herring leave fresh and brackish nursery grounds when they are about 5 cm (2 inches) long before they begin to migrate out to sea.

DIET: Blueback herring feed on small п¬Ѓshes, copepods, and small shrimps.

Natural History

Blueback herring are an anadromous species which form schools along the coastline and then begin to approach the shore in late spring to enter freshwater to spawn. Spawning occurs in fast moving, shallow water in the main stem of river tributaries. Juvenile blueback herring normally remain in the same watershed throughout the summer and fall and then migrate to the sea.

Conservation

Currently, a River Herring Conservation Plan is being developed and implemented for the management of alewife and blueback herring. The two species of herring are more commonly called “River Herring” by the Atlantic States Marine Fisheries Commission (ASMFC) and the National Marine Fisheries Service (NMFS).

www.fws.gov

Classification & Distribution

  • complete development (egg, larva, pupa, adult)

The Diptera have traditionally been divided into three suborders:

  • Nematocera (flies with multisegmented antennae)
  • Brachycera (flies with stylate antennae)
  • Cyclorrhapha (flies with aristate antennae)

In some newer classifications, Brachycera includes the Cyclorrhapha.

Distribution: Abundant worldwide. Larvae are found in all fresh water, semi-aquatic, and moist terrestrial environments.

Worldwide Number of Families Number of Species

Life History & Ecology

The order Diptera includes all true flies. These insects are distinctive because their hind wings are reduced to small, club-shaped structures called halteres — only the membranous front wings serve as aerodynamic surfaces. The halteres vibrate during flight and work much like a gyroscope to help the insect maintain balance.

All Dipteran larvae are legless. They live in aquatic (fresh water), semi-aquatic, or moist terrestrial environments. They are commonly found in the soil, in plant or animal tissues, and in carrion or dung — almost always where there is little danger of desiccation. Some species are herbivores, but most feed on dead organic matter or parasitize other animals, especially vertebrates, molluscs, and other arthropods. In the more primitive families (suborder Nematocera), fly larvae have well-developed head capsules with mandibulate mouthparts. These structures are reduced or absent in the more advanced suborders (Brachycera and Cyclorrhapha) where the larvae, known as maggots, have worm-like bodies and only a pair of mouth hooks for feeding.

Adult flies live in a wide range of habitats and display enormous variation in appearance and life style. Although most species have haustellate mouthparts and collect food in liquid form, their mouthparts are so diverse that some entomologists suspect the feeding adaptations may have arisen from more than a single evolutionary origin. In many families, the proboscis (rostrum) is adapted for sponging and/or lapping. These flies survive on honeydew, nectar, or the exudates of various plants and animals (dead or alive). In other families, the proboscis is adapted for cutting or piercing the tissues of a host. Some of these flies are predators of other arthropods (e.g., robber flies), but most of them are external parasites (e.g., mosquitoes and deer flies) that feed on the blood of their vertebrate hosts, including humans and most wild and domestic animals.

Physical Features

Immatures:

  • Culiciform
    • Head capsule present with chewing mouthparts
    • Legs absent
  • Vermiform (maggots)
    • Without legs or a distinct head capsule
    • Mouthparts reduced; only present as mouth hooks

Adults:

  • Antennae filiform, stylate, or aristate
  • Mouthparts suctorial (haustellate)
  • Mesothorax larger than pro- or metathorax
  • One pair of wings (front); hind wings reduced (halteres)
  • Tarsi 5-segmented

Economic Importance

The Diptera probably have a greater economic impact on humans than any other group of insects. Some flies are pests of agricultural plants, others transmit diseases to humans and domestic animals. On the other hand, many flies are beneficial — particularly those that pollinate flowering plants, assist in the decomposition of organic matter, or serve as biocontrol agents of insect pests.

Major Families

Biting flies: In most cases, only the adult females take blood meals.

      • Culicidae (mosquitoes) — may spread malaria, encephalitis, yellow fever, filariasis, and other diseases.
      • Tabanidae (horse flies / deer flies) — may spread tularemia, loiasis, trypanosomiasis, and other diseases.
      • Simulidae (black flies) — may spread human onchoceriasis and leucocytozoon infections of poultry.
      • Psychodidae (moth flies) — may spread leishmaniasis, sand fly fever, and other diseases.
      • Ceratopogonidae (punkies, no-see-ums) — small but vicious biters that have been linked to the spread of several roundworm, protozoan, and viral pathogens in humans and other animals.
      • Muscidae (House flies) — these are among the most cosmopolitan of all insects. Some species have biting mouthparts, others are merely scavengers. Diseases such as dysentery, cholera, and yaws may be transmitted on their feet and mouthparts.

Herbivores: larvae feed on plant tissues.

      • Cecidomyiidae (gall midges) — some induce the formation of plant galls; others are scavengers, predators, or parasites. This family includes the Hessian fly, Mayetolia destructor.
      • Tephritidae (fruit flies) — many species are agricultural pests; such as the apple maggot, Rhagoletis pomonella.
      • Agromyzidae — most larvae are leaf miners, some are stem and seed borers. Several species are agricultural pests.
      • Anthomyiidae — many species are root or seed maggots.

Scavengers: larvae feed in dung, carrion, garbage, or other organic matter.

      • Drosophilidae (pomace flies) — feed on decaying fruit.
      • Tipulidae (crane flies) — larvae live in soil or mud.
      • Calliphoridae (blow flies) — larvae feed on garbage and carrion; includes the screwworm, Cochliomyia hominivorax.
      • Chironomidae (midges) — aquatic larvae usually live in the mud and feed on organic matter.
      • Sarcophagidae (flesh flies) — larvae typically feed on carrion. Some species may cause human myiasis.
See also:  Pyrethrins and its cousins: a veterinary perspective on the good, the bad and the ugly - Dave s Garden

Predators: adults and/or larvae attack other insects as prey.:

      • Asilidae (robber flies) — general predators of other insects.
      • Bombyliidae (bee flies) — predatory larvae; adult bee mimics.
      • Empididae (dance flies) — adults are predatory.
      • Syrphidae (flower flies) — some larvae are aphid predators; most adults mimic bees or wasps.

Parasites: larvae are parasites or parasitoids of other animals.

      • Tachinidae — parasitoids of other insects. Several species are important biocontrol agents.
      • Sciomyzidae (marsh flies) — larvae parasitize slugs and snails.
      • Oestridae (bot flies / warble flies) — larvae are endoparasites of mammals, including humans.
      • Hippoboscidae (louse flies) — adults are blood-feeding ectoparasites of birds and mammals.

Bug Bytes

  • Although they have only two wings, flies are among the best aerialists in the insect world — they can hover, fly backwards, turn in place, and even fly upside down to land on a ceiling.
  • Flies have the highest wing-beat frequency of any animal. In some tiny midges, it may be as high as 1000 beats per second. Male mosquitoes are attracted by the wing-beat frequency of a virgin female.
  • Larvae of some shore flies (family Ephydridae) live in unusual habitats that would kill other insects. For example, Ephydra brucei lives in hot springs and geysers where the water temperature exceeds 112 degrees Fahrenheit; Helaeomyia petrolei develop in pools of crude oil; and the brine fly, Ephydra cinera, can survive very high concentrations of salt.
  • The arista in the antenna of higher flies is an air speed indicator. It allows the insect to sense how fast it is moving.
  • As they mature, black fly pupae become inflated with air. Upon emergence, the pupal skin pops open and the adult fly floats to the water surface inside a bubble of air. It never even gets its feet wet!
  • The little scuttle fly, Megaselia scataris (Phoridae), is truly an omnivore. It has been reared from decaying vegetation, shoe polish, paint emulsions, human cadavers pickled in formalin, and even lung tissue from living people.

© 2020 by John R. Meyer
Last Updated: 23 January 2020

projects.ncsu.edu

Freshwater invertebrates

Introduction

New Zealand’s streams are home to hundreds of tiny animals that live on and under rocks, waterplants, wood or debris. These animals include insects, crustaceans such as freshwater crayfish (koura), molluscs such as snails and mussels, worms and leeches.

They range in size from less than 1 mm long to over 10 cm long and can often be hard to see at first glance. Together these types of animals are called ‘macroinvertebrates’, meaning they have no backbones and can be seen without a magnifying glass or microscope.

Species

New Zealand has over 200 species of freshwater macroinvertebrates, with many species still awaiting discovery. They live in a range of environments, from the muddy bottoms of lowland streams to the gravelly streams of our mountain forests. They make up a large part of New Zealand’s biodiversity.


Adult mayfly

Macroinvertebrates are adapted to feed on a wide range of different things:

  • Some feed on rotting leaves and wood,
  • Some graze on algae (like cows grazing on grass),
  • Some filter food out of the water as it drifts past; and
  • Some catch and eat other macroinvertebrates.

Macroinvertebrates are often surveyed as part of water quality testing – as the type and number of individuals found in an area can be related directly to water quality. In good quality streams, it is possible to find more than 30 types of macroinvertebrates in a small area, and thousands of individuals within just one square metre of streambed.

Macroinvertebrates, such as mayflies, stoneflies, caddisflies and crayfish are usually found in healthy streams, macroinvertebrates such as worms, midges, snails and leeches are more tolerant of polluted or muddy streams.

Many species spend their juvenile stage in the stream and then emerge onto land as they develop into adults. Some of these species need stream-side plants to complete their life cycles.


Freshwater mussel

The next time you visit a stream, pick up a rock or object from the stream, look closely and see how many different macroinvertebrates you can find.

Water surface bugs

Water surface bugs like Hydrometra and Microvelia skate around the top of ponds or backwaters. They have mouths shaped like a beak or tube.

Backswimmers and waterboatmen

Backswimmers and waterboatmen swim in ponds, lakes and slow-flowing streams. You can find lots of them in rivers after long dry spells.

Diving beetles

Diving beetles are usually found in slow-flowing waters, particularly weedy ponds. These beetles have hard covers over their wings which they use to trap air bubbles for breathing. Some have special swimming hairs on their legs.

Dragonflies

Dragonfly larvae have wide, chunky bodies and an extendible jaw. They are found in a wide range of stream types in low numbers and are most common in lakes and ponds.

Snails

Snails like slow-flowing waters where there are lots of things like algae to eat. Snails can control the amount of slime on some riverbeds.

Leeches


Koura

Leeches are common in New Zealand, especially in weedy streams. Native New Zealand leeches don’t feed on people but prey on other stream invertebrates. Their bodies are very flexible and they move like caterpillars.

Freshwater shrimps

Freshwater shrimps, particularly the widespread Paratya, love weedy streams and estuaries. They feed constantly, so are interesting to watch.

Damselflies

Damselfly larvae live in the water; as adults they live on land. They have thin bodies, extendible jaws and three tail gills. They prey on other bug.

Mayflies

Mayfly larvae such as Nesameletus have three feather-like tails, which help them swim quickly through the water, and feathery gills along both sides of their bodies that they use to breathe.


Large swimming mayfly, larva

They are fussy about the water they live in and like cool, clean, well-aerated waters to live in. Polluted water can cause deformations to their wings and clog up their gills, making it hard for them to fly and breathe.

Caddisflies

Caddisflies include many species, some build sophisticated ‘houses’ from stone, sand or plants; others are ‘free-living’. Watch out for Triplectides, which lives inside bits of stick, Helicopsyche, which builds a spiral case out of sand, and the smoothcased Olinga, which appears in clean-water streams.

The adults resemble moths and range in size from just a few mm to about 8 cm (if you include their long antennae!)

Dobsonflies

Dobsonflies or toe-biters are the largest of our stream insects and are most common in good quality stony streams. They have leg-like gills along their body and biting jaws, which can give human fingers a good nip! They are the only representatives of their family in New Zealand.

Stoneflies

Stonefly nymphs like those of the long-tailed Zelandoperla have two tail strands. Only the green stonefly Stenoperla has gills along the sides of its body – many have gills between the tails. Stoneflies are most common in fast-flowing, stony-bed streams with cool water.

Mosquitos and sandflies

Only the female of both mosquitoes and sandflies bite. Sandflies use our blood to help produce eggs, which are then laid under stones and plants in flowing water.

Mosquito larvae start their life in standing water such as pools on a flooded forest floor. There are 13 native species of mosquito (plus 3 introduced ones), and about 11 different species of sand fly in New Zealand.

Threats


Female damselfly

  • Removal of native bush from stream margins.
  • Loss of habitat from land development and wetland drainage.
  • Habitat modification or changes to water quality from land development, run-off and discharges of contaminates and sediments.
  • Water abstraction – take too much and there may not be enough left for them to live in!

You can help


Forest stream — a typical habitat for freshwater invertebrates

  • Protect their habitats by maintaining flow and water levels.
  • Protect stream-side vegetation and forests in the catchments. Fence off stream edges from stock and plant alongside streams.
  • It is illegal to move freshwater plants and animals between waterways, but tranfers may occur by accident. Before you move to a new spot, make sure you clean fishing gear, trailers, boots etc.

Related

New Zealand Threat Classification System (NZTCS)

The New Zealand Threat Classification System is used to assess the threat status of our taxa (species, subspecies, varieties and forma).

www.doc.govt.nz

Striped furrow: adult lifestyle and larvae in fresh water

Click a marker above to learn about the mullet and its anatomy.

Adipose Eyelid: As they mature, mullet grow an adipose eyelid. This is a transparent fatty tissue covering the eye, which leaves a narrow slit over the pupil.

Dorsal Fins: Mullet are one of the few fish species with two dorsal fins. They are considered a ray-finned fish, because the fins are composed of webs of skin supported by bony spines, rather than fleshy lobed fins. The mullet’s first dorsal fin contains 5 sharp spines, while the second has 8 soft rays.

Anal Fin: One of the easiest ways to identify a striped mullet is by the number of anal fin rays. The striped mullet’s fin has 8 rays, whereas the white mullet has 9.

Gizzard: Mullet have strong stomachs, similar to gizzards, and long intestines, allowing them to thrive on a primarily vegetarian diet.

Mouth: Mullet have a distinctively shaped triangular mouth with several rows of small teeth.

Gill Rakers: Typically, fish use their gill rakers to filter out debris from water as it passes over their gills while breathing. For mullet, they serve an additional purpose, allowing them to filter out things they want to eat. This includes algae, plankton, and various other vegetation.

Lateral Line: Mullet do not have an obvious lateral line — the organ most fish use to detect variations in water currents.

Eyes: Two bulbous eyes on stalks sit either side of the rostrum. These are compound eyes which have panoramic vision and are very good at detecting movement.

Chela: The first two pairs of pereiopods have claws or chela. The chela can grasp food items and bring them to the mouth. They can also be used for fighting and grooming.

The mullet’s body is roughly torpedo-shaped with a round head and small mouth with inconspicuous teeth and a blunt nose. The lips are thin, with a bump at the tip of the lower lip. Pectoral fins are short, not reaching the first dorsal fin. The origin of the second dorsal fin is posterior to the origin of the anal fin. The lateral line is not visible.

This mullet is often confused with the white mullet, Mugil curema. However, the white mullet has scales extending onto its soft dorsal and anal fins while the striped mullet does not. They may also be identified by the anal ray fin count — 8 for the striped mullet and 9 for the white mullet.

The body is grayish olive to grayish brown, with olive-green or bluish tints and sides fading to silvery white towards the belly. Dark longitudinal lines are formed by dark spots at the center of each scale on the upper half of the body, and run the length of the body. Young fish smaller than 6 inches (15 cm) in length lack stripes. There is a large dark blotch at the base of the pectoral fin. The pigmentation in the iris is dispersed and brown, a character that also helps to distinguish it from White Mullet.

Size, Age and Growth:

The maximum recorded length of the striped mullet is 47.2 inches (120 cm), with a maximum weight of 17.6 pounds (8 kg). Lifespan is reported to range somewhere between 4 and 16 years. Maturity is attained at approximately 3 years of age, corresponding to lengths of 7.9-11.8 inches (20-30 cm). Females mature at a slightly larger size than males. Growth rates along the gulf coast of Florida increase from west to east, from the panhandle along the peninsula, likely due to the temperature increase. Most growth occurs during the spring and summer months. Adults grow at a rate of 1.5-2.5 inches (3.8-6.4 cm) per year. Females are larger and grow faster than males of the same age.

Mullet are diurnal feeders, consuming mainly zooplankton, dead plant and marine animal matter. Mullet have thick-walled gizzard-like segments in their stomach along with a long gastrointestinal tract that enables them to feed on many of the things in their diet. They are an ecologically important link in the energy flow within estuarine communities. Feeding by sucking up the top layer of sediments, striped mullet remove dead plant and marine animal matter and microalgae. They also pick up some sediments which function to grind food in the gizzard-like portion of the stomach. Mullet also graze on epiphytes and epifauna from seagrasses as well as ingest surface scum containing microalgae at the air-water interface. Larval striped mullet feed primarily on microcrustaceans. One study found copepods, mosquito larvae, and plant debris in the stomach contents of larvae under 35mm in length. The amount of sand and other food matter in the stomach contents increases with length indicating that more food is ingested from the bottom substrate as the fish matures.

The striped mullet is catadromous, that is, they spawn in saltwater yet spend most of their lives in freshwater. During the autumn and winter months, adult mullet migrate far offshore in large aggregations to spawn. In the Gulf of Mexico, mullet have been observed spawning 40-50 miles (65-80 km) offshore in water over 3,280 feet (1,000 m) deep. In other locations, spawning has been reported along beaches as well as offshore. Estimated fecundity of the striped mullet is 0.5 to 2.0 million eggs per female, depending upon the size of the individual.

The eggs are transparent and pale yellow, non-adhesive, and spherical with an average diameter of 0.72mm. Each egg contains an oil globule, making it positively buoyant. Hatching occurs about 48 hours after fertilization, releasing larvae approximately 2.4mm in length. These larvae have no mouth or paired fins. At 5 days of age, they are approximately 2.8mm long. The jaws become well-defined and the fin buds begin to develop. At 16-20mm in length, the larvae migrate to inshore waters and estuaries. At 35-45mm, the adipose eyelid is obvious, and by 50mm it covers most of the eye. At this time the mullet is considered to be a juvenile. These juveniles are capable of osmoregulation, being able to tolerate salinities of 0-35 ppt. They spend the remainder of their first year in coastal waters, salt marshes, and estuaries. In autumn, they often move to deeper water while the adults migrate offshore to spawn. However, some young mullet overwinter within the estuaries. After this first year of life, mullet inhabit a variety of habitats including the ocean, salt marshes, estuaries, and fresh water rivers and creeks.

Mullet Life Cycle:

Mullet spawn in salt water. Once hatched, the larvae make their way toward the coast and the juveniles settle in lower salinity water. They later school to freshwater estuaries where they grow to adults. In Florida, adults begin to spawn in the early fall October through January, returning to deeper salt water to spawn, as they cannot spawn in freshwater.

Includes excerpts from Florida Dept. of Natural History

taleoftwofish.com

Eastern Newt Information And Care

The eastern newt can live 12 to 15 years.

Photo by Brian Gratwicke

Notophthalmus viridescens

Size: Up to 5 inches long.

Life Span: About 12 to 15 years. Most eastern newts have lives divided into three distinct life stages. The first stage is the larval stage where the newt has gills and lives much like a tadpole. Although it is unclear how long this stage lasts, it finishes for most subspecies once the gills, shrinking as they become less functional, are absorbed back into the body. At this point the newt transforms into the eft stage, which is its land-dwelling stage. Totally terrestrial, an eft is bright orange with darker red spots outlined in black. After two or three years the eft finds a pond and transforms into the aquatic adult stage, which it retains for the rest of its life. At this point it becomes an olive green.

Range: This newt ranges throughout most of eastern North America from the Canadian Maritime Provinces west to the Great Lakes and south to Texas, Alabama, Georgia and Florida.

Natural Habitat: Deciduous and coniferous forests. Immature larvae and adult newts live in small bodies of fresh water usually with mud bottoms. Adults can survive on land if their aquatic habitat becomes unsuitable, such as during dry periods when water is low. The juvenile eft stage lives in lakeshore and woodland habitats, and it is often seen in forest litter on rainy nights.

Captive Housing: Up to three adults can be housed in a 10-gallon aquarium. Fill it halfway with dechlorinated water, and cover it with a screen lid to offer adequate ventilation. Water quality is important, and a filter is essential. Replace about 20 percent of the water weekly. Water temperatures should stay between 60 and 70 degrees Fahrenheit. A haul-out area is also required. Make one using driftwood, cork bark or basking platforms, such as those used for turtles. Plastic or live plants can provide aquatic hiding places in addition to a submerged cave, such as a clay pot or other heavy hiding spot.

Three efts can be housed in a 10-gallon terrarium. Use soil or coconut fiber for bedding, and include a few hiding places. Provide a water bowl about 2 inches deep and about 6 inches in diameter along with daily light misting. A full-spectrum fluorescent lamp with a low UVB output suitable for amphibians can be provided for simulated sunlight, and it enhances the look of both habitats.

Diet: Mainly carnivorous. Regardless of their life stage, they can be fed red worms, live or frozen brine shrimp, earthworms, and commercial amphibian diets. Remove any uneaten food to keep their habitats clean.

What’s Available: Commonly found throughout most of their range, wild-caught newts comprise the majority of pet trade offerings. Red-spotted newts (N. v. viridescens) are the most common subspecies in the pet trade. Some are captive bred, but numbers are still too low to provide a viable alternative to field-collected newts. REPTILES

Four Subspecies

  • The red-spotted newt (N. v. viridescens) is the most widespread and most frequently found subspecies in the pet trade. It has a row of small red-orange spots outlined in black going down the side of its body.
  • The central newt (N. v. louisianensis) is found along the southern and western boundaries of the species’ range. It usually lacks the red markings.
  • The broken-striped newt (N. v. dorsalis) is found in the Carolinas and has red-orange markings that look like dashes.
  • The peninsula newt (N. v. piaropicola) can be found in the Florida Panhandle. Typically skipping the eft stage, it metamorphoses right into an aquatic adult and is commonly neotenic. Larvae transform straight into sexually mature adults, but they retain the external gills.

This newt is capable of locating its home pond through true navigation using its sense of smell and a light-dependent magnetic compass built into its body.

www.reptilesmagazine.com

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