It was November 2014 since my last note. Too long ago. And much needs updating and publishing
Already prior to 2014 I have been monitoring vernal pools and herpetofauna in a number of sites other than Neyagawa-NHS and the 14 Mile Creek (both in Oakville). All monitoring results and community , water chemistry and plankton observations in this area are going to be organized as webpages by site under the general heading of “Vernal Pools & Herpetofauna“. I hope all the results up to December 2015 will up in the next few weeks.
In my surveys, many times, I find changes in the state of habitats and communities due to anthropogenic or natural events which are important to log as part of the history of the sites affected. These entries will be collected under the general heading “Site Survey Notes“.
Exiting blog entries will be expanded or copied into these new webpages. Blogs will be used for brief updates before they form part of the main website stream.
On August 2014 I was able to meet with Frank Laconte and Kristina Parker at the Town of Oakville. The meeting was facilitated by Mark Chris -. Director of the Parks and Recreations Dept. of the Town of Oakville.
In that meeting I submitted the following presentation. Note that the Google images used in the presentation can not be printed or further distributed. Anyone interested in the details can request the .kmz files for further analysis (For security reasons .kmz files can not be downloaded to WordPress).
The mapped overlays, as far as the extent of the specifically designated vegetation/tree boundaries are concerned, are close to mapped and measured locations, but nonetheless approximations.
The areas of concern are summarized over the boundary map of the Neyagawa Site of the NHS submitted in the North Oakville Subwatershed Study that forms the basis of the boundaries and alignments of the development sites with the NHS.
The boundaries in the zone closer to 6th line (right side of the map) have certainly not been properly implemented, perhaps there is the chance of some enhancement of the boundaries around the central area of concern where they missed to identify a MAM containing the fire bush that connects the SWD at the time this boundaries were laid out. Plus, this is the area where the vernal-autumnal pond is located. One can hope to negotiate for the trail to be on the outside of the treeline to safeguard these features. (edited excerpt of correspondence with Conservation Halton).
We will have to wait to see what Conservation Halton, the developers and the Town will eventually produce and if it will have any resemblance to the promises made during the North Oakville Trail Plan consultations.
Neyagawa spring 2013 survey results part 1 2013-05-08 is the link to a copy of a preliminary report of observed and potential ecosystem disturbances, as well as, the identification of new species-habitat connections observed in at the periphery of the Neyagawa NHS. Copy submitted to the Oakville Town May 8 2013.
This year’s visit to this amphibian breeding pond helped consolidate the presence of several invertebrate species, as well as, serve as an indication of the variability of the number and kind of species making use of the spring conditions of this vernal pool.
Pond characteristics and surrounding vegetation
The longest axis of the vernal pool has a west-east alignment measuring 28m. it is pear-shaped with a maximum width of 15m to the west and 12.7m to the east; and about 12m in its shortest width (see Figure 1, north upwards ). Water depth at maximum fill reaches about 60 to 80cm deep about 1 to 1.5m off its southern edge (see Figure 2, image rotated counter-clock wise). On may 11, depths measured were only around the 60cm to 40cm. The muck and leaf detritus layer is in the range of 25cm on the western edge to 17cm on the eastern edge. The underlying mineral soil layer below the muck is made of a heavy glay clay (Glay1 8/N) containing only a very small proportion of sand and gravel and less than 1% clay mottles. Also shown in Figure 2. is the few location of submerged grass.
Figure 3 (north is up). maps the location and characteristics of trees, shrubs and forbs within 5m of the vernal pool. Of significance is the presence of two elms(probably Rock Elms Ulmus thomasii) with bdh of 40 to 50cm and 16 to 20m high. Elms this tall are very unusual. A cluster of young Rock elms – with bdh in the range of 10 to 15 cm, are growing in the proximity of these two older elms. Why these group of elms has remained unaffected by Dutch-elm disease is unclear, when just less than 100 meters to the west, clusters of dead elms attest to the effect of the elm disease. Notice the encroachment by ash and maple on the south-eastern bank of the pool.
Account of species detected on April 21 2013 (visual survey)
Amphibian tadpoles: fewer overwintering Green frog tadpoles (~100mml; Lithobates clamitans) were observed this spring compared to last year.
This year, at least two, if not three species of amphibians laid eggs in this pool.
Most abundant eggs masses were from, what seems to be, Wood frogs (Lithobates sylvatica).
Characteristic Yellow-spotted salamander egg masses (Ambystoma maculatum, white eggs in the early stages – acquiring symbiotic bacteria later in their development) were also laid close by or mixed with the frog egg masses. [Top picture taken on April 21st, bottom picture taken in May 7. Notice in the bottom image the snail on the lower edge to the right of center (possibly Radix auriculata)].
Small isolated egg mass with only a few large eggs without gelly capsule were also noticed. These egg masses were laid in more shaded areas and apart from all others. They could be blue-spotted salamander eggs (Ambystoma laterale).
- Like last year, Central Newts (Notophtalmus viridescens lousianensis) were also noticed in the pool.
- A predaceous diving beetle (Dysticus spp.) drawn to a cluster of gray velvet springtails of the Poduridae family.
- Only one occurrence of a large aquatic snail (?Radix auriculata) was noticed this year – compared to their relative abundance last year (see the Yellow-spotted salamander image above). Relatively large (about 10 to 20mm in diameter) snail egg sacs were found at the east end of the vernal pool. Last year’s egg sacs were smaller but were more frequently found.
Account of species detected between May 7 and May 11 2013.
- One adult Green frog (Lithobates clamitans melanotus) seen on May 7.
- On May 11, a benthos sampling was performed. On surveying the location before and after benthic sampling, the following species were seen in the floating and submerged water layers:
Central Newt larva (see image below) and Central Newt adult (Notophtalmus viridescens louisianensis)
Swimming among the overwintering Green frog tadpoles was a number of smaller dark blackish tadpoles (~40mm; possibly wood frog tadpoles).
A variety of aquatic snails were found foraging on submerged and floating tree trunks and branches. Two kinds were seen: medium size (~1cm long) with pointed conical shells (Stagnicola spp.?), and flat coiled with ridges only a few millimeters in diameter. Also noticed was a large number of small gelly spherules on the mosses (?eggs).
Dobsonfly larva, Hellgrammite (~25 to 30mm) on underside of a submerged branch (Corydalus spp.). An indicator of relatively pure and undisturbed conditions.
Benthos Sampling results: Will be reported in an upcoming blog entry
Account of species absent in the 2013 survey compared to the 2012 spring survey.
- This spring there was no indications of the following species:
Leopard Frogs(Lithobates pipiens)
Midland Painted Turtles (Chrysemis picta marginata)
Water conditions for this spring
|DATE||TEMP ('C)||BANK SOIL TEMP ('C)||pH||CONDUCTIVITY (uS/cm)||ORP (mV)||Alkalinity (ppm)||Phosphate (ppm)||Nitrate (ppm)||Hardness (ppm)||Turbidity (FTU)|
|21 April 2013||8||5||7.3||245||182||110||>4||nd||250||84.7|
|11 May 2013||14||8.1||340||175||<1||nd||5.92?|
The following images represent some of the organisms recorded in a 500mL water sample colleceted on March 25 from the littoral water and leaf litter of Pond #1. It also includes organisms photographed during the survey but not collected.
The pictures are organized Taxonomically:
Hydrozoa: Hydra spp. – 3 to 12mm long
Molluscs: Water snail – 20mm long
Arthropods are represented in this pond by the Crustaceans Orders: Cyclopoda, Ostracoda, and Amphipoda, as well as, the Hexapod Orders: Adephaga, Mixophaga and Polyphaga Coleoptera, Hemiptera, and Ephemeroptera.
Crustaceans- Cyclopoda – Cyclops spp. – 0.1 to 0.5 mm
Amphipoda – Scud – Hyallela azteca complex – 5 – 7mm
Several egg masses were found attached to the leaf litter in the pond. These egg masses varied in appearance and texture as well as, in the size of the eggs it contained. The eggs in the water sample were observed from the day they were collected on March 25 until April 27. The water sample was kept at 13C to 16C and exposed to daylight through a window located two meters away from the sample.
1) Two translucent ochre single layered plastic cartouches with egg chambers about 1mm in diameter were found attached only to oak leaves. These eggs were the first ones to develop into recognizable morulae by April 4. Species unknown.
cartouche illuminated from the top (25.iii.2012)
Morulae after 20 days (04.iv.2012)
recognizable snail embryos two days later (16.iv.2012)
well-developed snail before hatching (21,iv,2012). By April 24 all snails had hatched.
The attached Acrobat pdf file (Table of Species), contains a list of Trees, Shrubs, Forbs, Ferns, Grasses, Sages and Fungi identified at the Neyagawa Forest System between 2010 and 2012.
The identification of some shrubs is tentative, the sage and grass species are incomplete, and that of Fungi needs to be verified.
Polygons refers to the way the forest system was subdivided for study purposes. These polygons partially correlate with specific forest types and post disturbance stages.
Survey 2012 to 2013
Spring Peepers Pseuacris crucifer
Leopard Frog Lithobates pipiens
Tadpoles (approximate 70 to 75mm long); very possibly overwintering L. pipiens tadpoles.
Red-spotted Newt Notophtalmus viridescens viridescens
Red-spotted Newt Notophtalmus viridescens viridescens
Midland Painted Turtle Chrysemis picta marginata
Midland Painted Turtle Chrysemis picta marginata
Eastern Garter Snake – Thamnophis sirtalis sirtalis
The water quality factors measured were pH, alkalinity (ppm, indicates buffering capacity), hardness (ppm, indicates content of polyvalent cathions), TDS (ppm total dissolved solids, indicates ions in solution)
|POLYGON & LOCATION||pH||Alkalinity (ppm)||Hardness (ppm)||TDS (ppm)||Water Temperature (C)|
|Polygon I, WP 68b (Main stream) MARCH 25||6||80||200||615||nd|
|POLYGON I, WP 52 (VERNAL) MARCH 14||5||20||100||nd||nd|
|POLYGON I, WP 12 (VERNAL) MARCH 14||5||20||100||25||3 TO 6|
|POLYGON I, WP 38a (VERNAL) MARCH 14||4.5||20||100||25||5|
|POLYGON 1, WP 47 (POND#1) MARCH 14||5||40||100||77||5|
|POLYGON 1, WP 47 (POND#1, rain fed only) MARCH 25||6||80||250||156||7|
|POLYGON I, WP 72 (FEN, central sage swamp) MARCH 14||5||40||200||142||7|
|POLYGON III, WP P2 (POND#2) MARCH 25||6||100||80||80||nd|
|POLYGON III, WP P3 (POND#3/MARSH)||6||20||<50||130||nd|
|POLYGON IV, WP 81 (SWD) MARCH 23|
|POLYGON V, WP ABA (MARSH) MARCH 23||5||20||50||34||nd|
|POLYGON V, WP 72 (BROOK, marsh draining stream) MARCH 23||5||<20||<50||38||nd|
Observations made during Jefferson Salamander breeding period in a very early spring with unusually high temperatures and after a very mild winter with rain rather than snow fall.
14, 23 & 25 March 2012 observations:
- Vernal Pools:
- No evidence of salamander egg masses in any of the vernal pools.
- Noticed the presence of a finger-nail clam species (Spehariidae) in vernal pools close to Neyagawa Road west of the Neyagawa Forest stream (broadly flooded by stream and road runoff). No evidence of clams was noticed in all other vernal pools (that doesn’t mean they are not there). These clams were present in ponds – see below.
- Rain fed only ponds
- Pond #1 – Located in the forest close to the eastern edge of the forest at WP 47,
- March 14: the presence of at least 30 or more relatively large tadpoles at a prehind leg stage.
- March 25: two tadpole captured and measured. 70 – 75mm long, 27 – 30mm body length, 42 – 43mm tail length, 15 – 18mm body width, and 10 – 12mm body hight.
- The tad poles might be hibernating Green frog tadpoles (Lithobates clamitans) (too small to be bull frog tadpoles at the same stage?).
- March 25: Basking single individua of
- Leopard frog (L. pipiens) and
- Spotted turtle (Clemmys guttata; endengered)
- March 25: Water snails (not yet identified), Water-striders (Gerridae), Backswimmer bug (Notonectidae), Predaceous Diving beetles (Dysticidae), and a few Whirling beetles (Gyrinidae).
- Pond water sample including leaf litter taken from the southern edge of the pond ~500mL.
- Examination of the sample between March 25 and April 5 revealed the presence of :
- Finger-nail clams (Spehariidae)
- three specimens ranging from 2mm to 7mm in length.
- by April 2nd/3, 3 more small clams have been observed, probably buried in the muck now large enough to become evident (1.5 to 3mm)
- April 5, all clams collected and stored in 70% Isoporopanol.
- 7 small calms (2.1 to 2.4mm)
- 2 larger clams (5.8 and 7.4mm)
- Active Podocopid Ostracoda (one or two possible species, 0.2mm long)
- by April 3rd, specimens detected rangefrom about .5mm to 2mm.
- evidence of empty shells keeps increasing with the passing of days
- April 3rd, observed one less then a tenth of a mm specimen.
- April 4, pictures of a shell showing the muscle scar pattern consistent with the specimen belonging to the Cypridacea superfamily and possibly of the genus Paracypris spp.
- April 5, two specimens collected (~1mm)
- Small-Minnow-Mayfly larvae (Callibaetis spp.)
- 6.5mm long; two such larvae in the sample
- by April 2nd, both have molted once and are reaching 7 to 8mm
- Freshwater shrimp (Amphipoda, Hyallela azteca complex)
- one light ochre specimen in the sample ~5 to 6mm (has a characteristic black rings in the base of the last antennal segment of the anterior pair).
- by April 2nd, the specimen has molted once and has become of a darker grayish colour.
- a second specimen found by April 3; same size as the first one.
- Hydra (Hydrozoa, Hydra spp.)
- green specimens with 5 tentacles, a total of 3 specimens observed
- by April 2nd, one specimen has a younger budding one on its side.
- by April 3rd, this specimen has moved about 6cm to a new location
- Green spheroid “cysts” unidentified
- 5 to 6 such globules
- by April 2nd, only 3 are left
- by April 3rd, only one left
- Jelly masses (two, a few cm long) consisting of ~1 mm transparent eggs with a white aggregate in the centre.
- no appreciable change in the eggs by April 2nd
- by April 3rd, one of the egg masses contains an active prodding translucent plychaete about 2 to 2.5mm long with pairs of long seate. (Bristleworm)
- no rotating motion was noted in the egg’s central aggregate
- Hard translucent moulded amber casing containing a layer of eggs ~ 1mm transparent eggs with a white aggregate in the centre.
- no appreciable change in the eggs by April 2nd
- by April 3rd, the center was filmed showing slow rotations that were consistent with a blastula
- One golden Pigmy Backswimmer (Pleidae, Neoplea striola)
- April 3rd, a highly conves golden coloured 2mm backswimmer. Its silvery abdomen consistent with air trapped in its abdominal surface.
- Identity confirmed April 5.
- Cyclopoids. Abundant in the sample. Possible two to three different species.
- A cycle of abundance and diminishment noticed for these small crustaceans.
- Protozoans. Abundant in the sample
- Blue-green Algae. Closteriaceae, Closterium spp. First specimen observed April5.
- Runoff and rain fed ponds
- Pond #2 (in the open pond located close to the eastern edge of Polygon III at WP P2).
- March 25: the presence of at least 20 or more relatively large tadpoles at a pre hind leg stage.
- March 25: No egg masses detected in the pond. March 25: Presences of at least 2 newts (Red transforming or Central newt; Notophthalmus viridescens).
- March 25: Water snails (not yet identified), Water-striders (Gerridae), Backswimmer bug (Notonectidae), and a large colony of Whirling beetles (Gyrinidae).
- Marshes with open water fed by runoff and rain
- Central Fen/Marsh in Polygon I at WP 72.
- March 14: Except for bacterial “clouds” there was no evidence of amphibian activity.
- March 25: Identification of an ant hill within the swamp.
- March 25: still no evidence of any amphibian activity.
- Polygon V. Marsh complex
- WP 74. Slow draining brook off the marsh in Polygon V. Mud chimneys. Non was taller than 2 to 3 inches. Central tube diameter ranges from 15 to 25mm. Two species are possible the Devil Crayfish (Camburus diogenes) or the Digger Crayfish (Fallicambarus fodiens). The habitat of both these species is threatened.
- WP 75 3 to 5 Chorus frogs (Psuedacris triseriata) heard in the marsh. WP 76 (boundary of the marsh with the open field to the south east). Evidence of a crayfish chimney.
- WP 79 (south edge of the marsh boundary with remnant tree line. Evidence of Spring Peeper (Pseudacris cruciifer).