Effects on Aquatic Insects of Forest Spraying with Phosphamidon in New Brunswick

1967 ◽  
Vol 24 (4) ◽  
pp. 823-832 ◽  
Author(s):  
C. D. Grant
Keyword(s):  
New Brunswick ◽  
Aquatic Insects ◽  
No Reduction ◽  
Number Of Individuals ◽  
Harmful Effects

No harmful effects on aquatic insects were detected in two New Brunswick streams after forest spraying with phosphamidon [Formula: see text] in 1962 and 1963. Comparison of one pre-spray and two post-spray series of bottom samples showed no reduction in number of orders (and families in the case of Diptera) and no abnormal decline in the number of individuals. In numbers and variety of insects emerging daily into stream cages and of insects drifting onto vertical screens in the streams, no changes were attributable to phosphamidon.

Effects of Forest Spraying with DDT in New Brunswick on Food of Young Atlantic Salmon

1967 ◽  
Vol 24 (4) ◽  
pp. 807-822 ◽  
Author(s):  
Miles H. A. Keenleyside
Keyword(s):  
Atlantic Salmon ◽  
New Brunswick ◽  
Aquatic Insects ◽  
Fish Food ◽  
Active Selection

Food in stomachs of young Atlantic salmon from the Northwest Miramichi River, N.B., changed following aerial DDT spraying of the surrounding watershed. Before spraying, young salmon typically ate immature aquatic insects, fry (underyearlings) concentrating on Diptera and small Ephemeroptera, and parr (overyearlings) on Diptera, Trichoptera, and all sizes of Ephemeroptera. Reduction of all aquatic insects by DDT was soon followed by resurgence of Chironomidae and other Diptera, and surviving fry fed heavily on these; parr fed on Diptera but also ate snails, worms, and fish, previously unimportant in their diet. Five years after the last spraying the pre-spray complexity of young salmon food was being approached. Trichoptera were slowest of the major fish-food types to reappear in stomachs.In fry stomachs Ephemeroptera, and in parr stomachs Ephemeroptera and Trichoptera, were relatively more abundant than in the surrounding stream fauna. Greater availability of these insects and active selection by fish are discussed as possible causes of these relationships.

scholarly journals Diversity and Distribution of Aquatic Insects in Streams of the Mae Klong Watershed, Western Thailand

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Witwisitpong Maneechan ◽  
Taeng On Prommi
Keyword(s):  
Water Quality ◽  
Aquatic Insects ◽  
Shannon Index ◽  
Insect Fauna ◽  
Water Quality Variables ◽  
High Species Diversity ◽  
Almost All ◽  
Number Of Individuals ◽  
High Diversity ◽  
Index Of Diversity

The distribution and diversity of aquatic insects and water quality variables were studied among three streams of the Mae Klong Watershed. In each stream, two sites were sampled. Aquatic insects and water quality variables were randomly sampled seven times in February, May, September, and December 2010 and in January, April, and May 2011. Overall, 11,153 individuals belonging to 64 families and nine orders were examined. Among the aquatic insects collected from the three streams, the order Trichoptera was most diverse in number of individuals, followed by Ephemeroptera, Hemiptera, Odonata, Coleoptera, Diptera, Plecoptera, Megaloptera, and Lepidoptera. The highest Shannon index of diversity of 2.934 and 3.2 was recorded in Huai Kayeng stream and the lowest was in Huai Pakkok stream (2.68 and 2.62). The high diversity of insect fauna in streams is an indication of larger microhabitat diversity and better water quality conditions prevailing in the streams. The evenness value was recorded as high in most sites. The high species diversity and evenness in almost all sites indicated good water quality.

Effects of Forest Spraying with DDT on Aquatic Insects of Salmon Streams in New Brunswick

1967 ◽  
Vol 24 (4) ◽  
pp. 769-805 ◽  
Author(s):  
F. P. Ide
Keyword(s):  
New Brunswick ◽  
Aquatic Insects ◽  
Late Summer ◽  
Bottom Fauna ◽  
Small Populations ◽  
Single Application ◽  
Severe Reduction ◽  
Large Populations

Sampling of emerging aquatic insects by cage-traps on a 24-hr basis showed the effects on the stream fauna of spraying forests with DDT at [Formula: see text] in June. Except for a few individuals that presumably emerged from unaffected pupae and nymphs, there was an interval of several weeks after spraying when no emergence occurred. From about the middle of August, however, large populations of very small insects, mainly chironomids, emerged in the spray year. The year after spraying, as compared with the spray year, there was an increased variety including some larger species.In following years there was further recovery by increase in larger forms through reproduction from residual small populations. The caddisflies recovered more slowly than other groups. After a single application of spray the fauna had practically recovered qualitatively in 2 or 3 years in some groups but usually not for 4 years or more in caddisflies. With a further similar spray applied within 3 years a reduction occurred equal in severity to that of the original spraying.From the standpoint of feeding of the young salmon, significant facts are: (a) the severe reduction in the bottom fauna of larvae and nymphs of all sizes in the first weeks after spraying; (b) the large populations of small larvae, mainly chironomids, developing in late summer of the spray year and so available to fry; (c) increasing numbers of larger insects the year after spraying and subsequent years.

Effects on Wild Young Salmon of Spraying DDT over New Brunswick Forests

1967 ◽  
Vol 24 (4) ◽  
pp. 731-767 ◽  
Author(s):  
P. F. Elson
Keyword(s):  
New Brunswick ◽  
Early Mortality ◽  
Young Fish ◽  
Single Application ◽  
Quantitative Measurements ◽  
Other Information ◽  
Size Groups ◽  
Parent Stock ◽  
Winter Cold ◽  
Harmful Effects

When DDT-in-oil was sprayed over large tracts of New Brunswick forest some of the spray got into drainage systems lying in the spray zones. As a result, many young salmon were killed and stocks were endangered.Most New Brunswick salmon spend 3 years in rivers before migrating to sea as smolts. The young fish can conveniently be divided into three size-groups, which are roughly comparable to each year of age. The groups are: underyearlings, small parr (over 1 year old but 10 cm and under from tip of snout to tip of extended tail fin), and large parr.Wild young salmon in unsprayed and sprayed streams were assessed for numbers in each size-group, abundance being expressed as population index = average number per 100 yards2 of stream bottom.DDT at[Formula: see text]. After such spraying young salmon of all size-groups were found in noticeably low numbers as compared with unsprayed situations. Underyearlings were only 2–10% as abundant (index reduced from 24 in places not affected by spray to less than 1 in most sprayed places), small parr only 30% (index reduced from 20 to 6), and large parr only 50% (index reduced from 12 to 6) as abundant.DDT at[Formula: see text]. After spraying at this dosage underyearlings were only about 50% as abundant as with no spraying; small parr were about 80% as abundant and large parr were affected hardly at all.DDT at[Formula: see text]applied twice. This was followed by low numbers of underyearlings, similar to those observed with a single application at [Formula: see text]. No equivalent data for parr are available but other information indicates effects similar to a single spraying with [Formula: see text].Downstream transport of the DDT-in-oil mixture was an important factor in extending the, harmful effects 30 or more miles below spray zones.Delayed mortality followed 4 to 6 months after the early mortality described above. It was associated with the onset of winter cold. It may have removed a large proportion of parr which survived early mortality but quantitative measurements of this factor were not made on wild populations.Reductions in numbers of young salmon were followed by declines in numbers of adults taken in fisheries and returning as spawners.With no spraying in subsequent years, promptness of recovery of young salmon populations depended primarily on abundance of parent stock.

Trichomycetes in aquatic insects from Prince Edward Island, Canada

2007 ◽  
Vol 85 (10) ◽  
pp. 949-963 ◽  
Author(s):  
D. B. Strongman
Keyword(s):  
New Brunswick ◽  
Aquatic Insects ◽  
Prince Edward Island ◽  
Species Complex ◽  
East Coast ◽  
High Tide ◽  
Distribution Patterns ◽  
The Usa ◽  
First Time ◽  
Unique Species

Trichomycetes, an ecological grouping of fungi and protists associated with the guts of aquatic arthropods, are distributed globally. The diversity of this unique species complex is, however, more completely documented in some parts of the USA and Europe than in Canada. Twenty species of trichomycetes were collected from insect hosts at six sites in Prince Edward Island, situated in the Gulf of St. Lawrence about 14 km off the east coast of New Brunswick. Five new species of Harpellales (Fungi, Kickxellomycotina), Caudomyces longicollis Strongman sp. nov. from Antocha sp. (Tipulidae), Legeriomyces minae Strongman sp. nov. from mayflies, and Smittium ditrichosporum Strongman sp. nov., Smittium insulare Strongman sp. nov., and Smittium tynense Strongman sp. nov. from chironomids are described. Smittium brevisporum L.G. Valle & Santam. and Smittium gracilis L.G. Valle & Santam., previously known only from Spain, are recorded for the first time in North America. A number of species of Harpellales and Amoebidiales (Phylum Mesomycetozoa) previously recorded from the region (P.E.I. and N.S.), and several that are common and widely distributed, were also recovered. Stachylina pedifer Lichtw. & M.C. Williams was collected from chironomids in a stream exposed to seawater during high tide. Trichomycete diversity is high on P.E.I., as it is in many regions where extensive surveys have been conducted, including islands such as Australia and New Zealand. More data from islands may help shed some light on distribution patterns for these obligate endobionts and provide some insights into mechanisms for dispersal.

Fish Losses After Forest Sprayings with Insecticides in New Brunswick, 1952–62, as Shown by Caged Specimens and other Observations

1967 ◽  
Vol 24 (4) ◽  
pp. 709-729 ◽  
Author(s):  
C. J. Kerswill ◽  
H. E. Edwards
Keyword(s):  
Atlantic Salmon ◽  
New Brunswick ◽  
Brook Trout ◽  
Lower Boundary ◽  
Single Application ◽  
Short Term ◽  
Free Living ◽  
Forested Area ◽  
Forested Areas ◽  
Harmful Effects

The survival of young Atlantic salmon and eastern brook trout, held in cages and free-living, was observed in New Brunswick streams inside and outside forested areas sprayed operationally and experimentally from aircraft with DDT and other insecticides for budworm control. DDT-in-oil in a single application at [Formula: see text] caused heavy loss of underyearling salmon and parr within 3 weeks. DDT-in-oil at [Formula: see text] had no apparent short-term effects on salmon parr, but killed many underyearlings; two applications 10 days apart were about as harmful as a single application at [Formula: see text]. DDD at [Formula: see text] and [Formula: see text], and malathion at [Formula: see text], were no more harmful to young salmon than DDT at [Formula: see text]. Replacing Stearman airplanes with larger aircraft in operational spraying and associated changes in spraying procedure sometimes caused heavy fish losses even for single applications of DDT at [Formula: see text]. Experimental spraying of phosphamidon-in-water at 1 lb/acre had no apparent harmful effects on young salmon and trout.Observations at a counting fence across the Northwest Miramichi 12 miles below the lower boundary of the forested area sprayed with DDT at [Formula: see text] in 1954 showed extensive killing of suckers and cyprinids; also, the numbers of these species moving through the fence were abnormally low for several years after spraying.Wild young salmon were found dead in streams when autumn water temperatures approached freezing after June sprayings of watersheds with DDT.

GRAIN APHIDS IN NEW BRUNSWICK: III. APHID POPULATIONS IN HERBICIDE-TREATED OAT FIELDS

1965 ◽  
Vol 43 (5) ◽  
pp. 789-794 ◽  
Author(s):  
Jean B. Adams ◽  
Margaret E. Drew
Keyword(s):  
New Brunswick ◽  
No Reduction ◽  
Aphid Populations

From similar initial populations, aphid infestations became higher in herbicide-treated areas of oats than in similar untreated areas. Fewer coccinellids were present in these treated areas. The inclusion of an aphicide with the herbicide applications held subsequent populations of aphids to the level of those in untreated plots. Although populations as high as 250 aphids per tiller occurred, no reduction in yields of grain or straw was found in 1962 or 1963.

A Fly of the Archaic Family Nymphomyiidae Found in New Brunswick in 1961

1964 ◽  
Vol 96 (1-2) ◽  
pp. 119-120 ◽  
Author(s):  
F. P. Ide
Keyword(s):  
New Brunswick ◽  
Aquatic Insects ◽  
Chemical Control ◽  
New Genus ◽  
Forest Protection ◽  
Small Stream ◽  
Canada Department ◽  
Fine Mesh ◽  
Control Section

Until now this family has been known only through one species Nymphomyia alba Tokunaga, found in Japan in 1932. The specimens taken in New Brunswick and shown in the exhibit differ strikingly from Nymphomyia and represent a new genus.With one exception, the thirty-eight individuals recovered from collections to date, were taken by fine-mesh screens set in the rapids of a small stream. These had been placed to catch casualties among aquatic insects drifting downstream following spraying of the adjacent forest with DDT. The spraying operation was of an experimental nature, carried out cooperatively by Forest Protection Limited, the Chemical Control Section, Canada Department of Forestry and the Fisheries Research Board of Canada.

Perceptual Learning of Vocoded Speech With and Without Contralateral Hearing: Implications for Cochlear Implant Rehabilitation

2020 ◽  
pp. 1-10
Author(s):  
Martin Chavant ◽  
Alexis Hervais-Adelman ◽  
Olivier Macherey
Keyword(s):  
Cochlear Implant ◽  
Perceptual Learning ◽  
Speech Signal ◽  
Training Phase ◽  
Monosyllabic Words ◽  
Low Pass ◽  
Contralateral Ear ◽  
Number Of Individuals ◽  
Insight Into ◽  
Vocoded Speech

Purpose An increasing number of individuals with residual or even normal contralateral hearing are being considered for cochlear implantation. It remains unknown whether the presence of contralateral hearing is beneficial or detrimental to their perceptual learning of cochlear implant (CI)–processed speech. The aim of this experiment was to provide a first insight into this question using acoustic simulations of CI processing. Method Sixty normal-hearing listeners took part in an auditory perceptual learning experiment. Each subject was randomly assigned to one of three groups of 20 referred to as NORMAL, LOWPASS, and NOTHING. The experiment consisted of two test phases separated by a training phase. In the test phases, all subjects were tested on recognition of monosyllabic words passed through a six-channel “PSHC” vocoder presented to a single ear. In the training phase, which consisted of listening to a 25-min audio book, all subjects were also presented with the same vocoded speech in one ear but the signal they received in their other ear differed across groups. The NORMAL group was presented with the unprocessed speech signal, the LOWPASS group with a low-pass filtered version of the speech signal, and the NOTHING group with no sound at all. Results The improvement in speech scores following training was significantly smaller for the NORMAL than for the LOWPASS and NOTHING groups. Conclusions This study suggests that the presentation of normal speech in the contralateral ear reduces or slows down perceptual learning of vocoded speech but that an unintelligible low-pass filtered contralateral signal does not have this effect. Potential implications for the rehabilitation of CI patients with partial or full contralateral hearing are discussed.

Canada, Nova Scotia, New Brunswick, and the Other British Provinces in North America

2009 ◽  
Author(s):  
James Silk Buckingham
Keyword(s):  
Nova Scotia ◽  
North America ◽  
New Brunswick ◽  
The Other
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