20 de fevereiro de 2020

Calvert County (MD) Dragonflies and Damselflies: Part Ten – Pennant Dragonflies of the Family Libellulidae

Family: Libellulidae (Pennants)

Due to the large number of species present for this family, I will be breaking down the family into smaller segments starting with the Pennant dragonflies. First some comments about the Family Libellulidae. For our area, this is certainly the dominant group of dragonflies in terms of the number of species and the overall observations in iNaturalist. An examination of the dragonfly observations for each of the three southern Maryland counties reveals that 88% or greater of the total number of observations for all dragonflies are comprised of skimmer (Libellulidae) dragonflies. For Calvert, Charles, and St. Marys Counties, the number of skimmer vs. total observations are 305/328, 147/166, and 44/50, respectively.

For myself, this is the first family of dragonflies in which I have made observational contributions to the Calvert County iNaturalist database. To date, I have submitted a total of 116 observations for 17 different species. Of the Calvert Pennant dragonflies, nine of the eleven observations for the Halloween Pennant are mine and also one of the five observations for the Four-spotted Pennant.

Of the six species listed below for southern Maryland from Richard Orr’s database, four of the six species can be found in all three southern Maryland counties. This includes two species on the S3 Watch List of the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”. The S2 State Rare Double-ringed Pennant is only known from Charles County.

Listed below are the Pennant species within the Libellulidae family that have been observed in at least one of the southern Maryland counties and a comparison of the two databases is made (as of February, 2020). As was done with the previous family, I have included with most species a note extracted from the book “Natural History of DelMarVa Dragonflies and Damselflies” by Hal White (reference 1). Of particular relevance for Calvert County, I have also included information on the four species of this group that were observed at the Cove Point LNG Property and reported in “2011-2012 Survey of the Dragonflies and Damseflies (Odonata) of the Cove Point LNG Property (Calvert County, Maryland” by Richard Orr (reference 2).

Four-Spotted Pennant/Brachymesia gravida
S3 Watch List (see below for definition)
A larger member of the family, it prefers coastal habitats including brackish areas. (1)
Cove Point adult abundance and flight period – common/17-Jun to 03-Sept. (2)
iNaturalist research grade observations:​ Calvert = 5 (Jun-Jul) St. Marys = 1 (Jun) Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles – present

Red-veined Pennant/Celithemis bertha
In southern Maryland, this species is only found at St. Marys State Park and was first discovered there in 2014. (Maryland Biodiversity website).
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – present Charles - X

Calico Pennant/Celithemis elisa
Some think that a better common name for this species would have been “Valentine Pennant” to call attention to the small, red heart-shaped markings that adorn the top of several abdominal segments of the males. (1)
Cove Point adult abundance and flight period – common/21-May to 22-Aug. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 2 (May-Jun)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Halloween Pennant/Celithemis eponina
The author says that this might be his favorite English dragonfly name because the name is so appropriate with the orange wings and brown spots. It was not until 1996 that the Dragonfly Society of America approved the idea of creating “common names” for dragonflies. The idea was not embraced by some dragonfly purists. (1)
Cove Point adult abundance and flight period – common/04-Jun to 11-Sept. (2)
iNaturalist research grade observations:​ Calvert = 11 (Jun-Aug) St. Marys = 1 (Aug) Charles = 5 (Jun-Sept)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Banded Pennant/Celithemis fasciata
S3 Watch List (see below for definition)
This species appears to be in decline. Ponds that have become loaded with algae due to over-fertilization from agricultural runoff is one possible explanation. (1)
Cove Point adult abundance and flight period – uncommon/04-Jun to 07-Jul. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0​ Charles = 5 (Jun-Jul)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Double-ringed Pennant/Celithemis verna
S2 State Rare (see below for definition)
The compound eyes of dragonflies contain thousands of facets, or ommatidia, that focus light coming from different directions. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 6 (Jun)
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – X​ Charles - present

Definitions from the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”:
S2 - Imperiled / State Rare — At high risk of extinction or extirpation due to restricted range, few populations or occurrences, steep declines, severe threats, or other factors. Typically occurring in 6-20 populations.

S3 - Vulnerable / Watchlist — At moderate risk of extinction or extirpation due to a fairly restricted range, relatively few populations or occurrences, recent and widespread declines, threats, or other factors. Typically occurring in 21-80 populations.

Publicado em 20 de fevereiro de 2020, 09:27 PM por rosalie-rick rosalie-rick | 0 comentários | Deixar um comentário

14 de fevereiro de 2020

Calvert County (MD) Dragonflies and Damselflies: Part Nine – Dragonfly Family Corduliidae

Family: Corduliidae
This is another family of dragonflies that is severely under-represented in the southern Maryland iNaturalist observational database. There is but a single observation in total for the three counties and that is for a Common Baskettail observed in Calvert County. Of the nine species listed below for southern Maryland from Richard Orr’s database, all nine can be found in Charles County, five of the species in St. Marys County, and five in Calvert County. A major consideration is that five of the nine species are listed on the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”. So while much work remains to be done in order to bring the iNaturalist observations closer to the definitive database of county sightings, the rarity of many of these species will probably require a specialized effort to find them.

Listed below are the species within the Corduliidae family that have been observed in at least one of the southern Maryland counties and a comparison of the two databases is made (as of January, 2020). As was done with the previous family, I have included with each species a note extracted from the book “Natural History of DelMarVa Dragonflies and Damselflies” by Hal White (reference 1). Of particular relevance for Calvert County, I have also included information on the four species of this family that were observed at the Cove Point LNG Property and reported in “2011-2012 Survey of the Dragonflies and Damseflies (Odonata) of the Cove Point LNG Property (Calvert County, Maryland” by Richard Orr (reference 2).

Common Baskettail/Epitheca (Tetragoneuria) cynosura
All damselflies and some dragonflies (darners) oviposit by using a sharp ovipositor to deposit their eggs within tough plant tissue. The thought is that most dragonfly families evolved away from this mechanism of egg laying. The female Common Baskettail extrudes her eggs into a gelatinous mass which becomes attached to floating objects in the water. (1)
Cove Point adult abundance and flight period – common/01-Apr to 14-Jun. (2)
iNaturalist research grade observations:​ Calvert = 1 (Apr) St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present ​ Charles - present

Prince Baskettail/Epitheca (Epicordulia) princeps
Dragonflies are aquatic insects for most of their lifecycle, but as adults they transition into terrestrial insects. Dehydration in the adults becomes a major problem throughout their terrestrial period. (1)
Cove Point adult abundance and flight period – rare/04-Jun. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles – present

Robust Baskettail/Epitheca (Tetragoneuria) spinosa
S1/S2 State Rare (see below for definition)
Baskettails underwent a classification revision in 1966 although not everyone has yet to accept the proposed revision. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – X Charles - present

Selys’ Sundragon/Helocordulia selysii
S2 State Rare (see below for definition)
The first known specimen of this species was collected in DelMarVa in 1937. It would be almost 70 years before the second record of the species was made in DelMarVa in 2006. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – X​ Charles - present

Uhler’s Sundragon/Helocordulia uhleri
This species has not been recorded for the DelMarVa peninsula. (1) It is only known from four counties within all of Maryland.
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – X Charles - present

Fine-lined Emerald/Somatochlora filosa
S2 State Rare (see below for definition)
The Great Cypress Swamp of DelMarVa forms the headwaters of the Pocomoke River and once covered an area of nearly 60,000 acres. The swamp is also known as the Burnt Swamp as a result of an eight year fire within its boundaries. Remnants of the Great Cypress Swamp can still be found in Trap Pond State Park in Delaware and in the Pocomoke River State Park of Maryland. These are among the few places where the Fine-lined Emerald can be found. (1)
Cove Point adult abundance and flight period – rare/29-Aug to 30-Sept. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – X​ Charles - present

Mocha Emerald/Somatochlora linearis
S3 Watch List (see below for definition)
For those interested in creating a life list for dragonflies, it is important to consider visiting different types of sites, different seasons, and even different times of day. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Treetop Emerald/Somatochlora provocans
S1 (see below for definition)
While some Emerald dragonflies are southern in their distribution, the majority are closer to a Canadian distribution and inhabit bogs, peat-stained streams, and alpine lakes. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – present​ Charles - present

Clamp-tipped Emerald/Somatochlora tenebrosa
Emeralds have a special allure for dragonfly enthusiasts because they are challenging to ID, are generally scarce, and even when present are almost always elusive. (1)
Cove Point adult abundance and flight period – uncommon/16-Jun to 11-Sept. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Definitions from the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”:
S1 - Critically Imperiled / Highly State Rare — At very high risk of extinction or extirpation due to very restricted range, very few populations or occurrences, very steep declines, very severe threats, or other factors. Typically occurring in five or fewer populations.
S2 - Imperiled / State Rare — At high risk of extinction or extirpation due to restricted range, few populations or occurrences, steep declines, severe threats, or other factors. Typically occurring in 6-20 populations.
S3 - Vulnerable / Watchlist — At moderate risk of extinction or extirpation due to a fairly restricted range, relatively few populations or occurrences, recent and widespread declines, threats, or other factors. Typically occurring in 21-80 populations.

Publicado em 14 de fevereiro de 2020, 04:39 PM por rosalie-rick rosalie-rick | 0 comentários | Deixar um comentário

11 de fevereiro de 2020

Calvert County (MD) Dragonflies and Damselflies: Part Eight – Dragonfly Family Macromiidae

Family: Macromiidae
There are only four known species of this family in the official Maryland state record. Only two of the four species are listed for southern Maryland and only one of those for Calvert County. Within the iNaturalist database, observations for species within this family are quite sparse for the entirety of Maryland. There are currently no observations recorded in iNaturalist for this family of dragonflies in the three southern Maryland counties.

Listed below are the two species within the Macromiidae family that have been observed in southern Maryland counties and a comparison of the two databases is made (as of January, 2020). As was done with the previous families, I have included with each species a note extracted from the book “Natural History of DelMarVa Dragonflies and Damselflies” by Hal White (reference 1). Of particular relevance for Calvert County, I have also included information on the single species of this family that was observed at the Cove Point LNG Property and reported in “2011-2012 Survey of the Dragonflies and Damseflies (Odonata) of the Cove Point LNG Property (Calvert County, Maryland” by Richard Orr (reference 2).

Stream Cruiser/Didymops transversa
Unlike their larval forms, adult dragonflies and damselflies do not walk. The adult legs are adapted for perching and catching prey, but not walking. (1)
Cove Point adult abundance and flight period – uncommon/21-Apr to 10-May. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present ​ Charles - present

Georgia River Cruiser/Macromia illinoiensis georgina
S3 Watch List (see below for definition)
The Georgia River Cruiser is almost indistinguishable from a closely related subspecies, the Illinois River Cruiser. The Illinois River Cruiser can be found in fast flowing streams of the Piedmont while the Georgia River Cruiser prefers slower moving Coastal Plain streams. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – present​ Charles - present

Definitions from the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”:
S3 - Vulnerable / Watchlist — At moderate risk of extinction or extirpation due to a fairly restricted range, relatively few populations or occurrences, recent and widespread declines, threats, or other factors. Typically occurring in 21-80 populations.

Publicado em 11 de fevereiro de 2020, 06:23 PM por rosalie-rick rosalie-rick | 0 comentários | Deixar um comentário

10 de fevereiro de 2020

Calvert County (MD) Dragonflies and Damselflies: Part Seven – Dragonfly Family Cordulegasteridae

Family: Cordulegasteridae
For the entire state of Maryland, there are only five known species of this family in the official state record. Of the five species, only two are in the iNaturalist database for southern Maryland with one each for Calvert and St. Marys Counties. The record for each of those species is the result of a single observation. Charles County has yet to be represented in iNaturalist for this family of dragonflies. Once again, much work remains to be done in order to bring the iNaturalist observations in closer harmony to the definitive database of county sightings.

Listed below are the species within the Cordulegasteridae family that have been observed in at least one of the southern Maryland counties and a comparison of the two databases is made (as of January, 2020). As was done with the previous families, I have included with each species a note extracted from the book “Natural History of DelMarVa Dragonflies and Damselflies” by Hal White (reference 1). Of particular relevance for Calvert County, I have also included information on the two species of this family that were observed at the Cove Point LNG Property and reported in “2011-2012 Survey of the Dragonflies and Damseflies (Odonata) of the Cove Point LNG Property (Calvert County, Maryland” by Richard Orr (reference 2).

Brown Spiketail/ Cordulegaster bilineata
S3 Watch List (see below for definition)
The Brown Spiketail was once thought to be a geographical or morphological variant of the Delta-spotted Spiketail, but analysis of the mitochondrial DNA has confirmed it is a separate species. (1)
Cove Point adult abundance and flight period – uncommon/31-Mar to 14-June. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present ​Charles - present

Tiger Spiketail/Cordulegaster erronea
S3 Watch List (see below for definition)
Female spiketails will hover over shallow water and then perform multiple dips of the abdomen vertically into the water like a pogo stick, each time depositing an egg into the stream bottom. (1)
iNaturalist research grade observations:​ Calvert = 1 (June) St. Marys = 0​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles – present

Twin-spotted Spiketail/ Cordulegaster maculata
Full grown larvae no longer feed in the weeks prior to emergence and the internal processes of metamorphosis occur during this stage. (1)
Cove Point adult abundance and flight period – rare/23 Apr to 10-May. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 1 (Apr)​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Arrowhead Spiketail/ Cordulegaster obliqua
S2 State Rare (see below for definition)
Traditionally, actual insect specimens were required to document species for identification and were then stored along with date and locality information. In some instances photographic records have been accepted for documentation purposes. The only record of this species on the DelMarVa peninsula is from a single photograph. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – present​ Charles - present

Definitions from the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”:
S2 - Imperiled / State Rare — At high risk of extinction or extirpation due to restricted range, few populations or occurrences, steep declines, severe threats, or other factors. Typically occurring in 6-20 populations.

S3 - Vulnerable / Watchlist — At moderate risk of extinction or extirpation due to a fairly restricted range, relatively few populations or occurrences, recent and widespread declines, threats, or other factors. Typically occurring in 21-80 populations.

Publicado em 10 de fevereiro de 2020, 08:26 PM por rosalie-rick rosalie-rick | 0 comentários | Deixar um comentário

09 de fevereiro de 2020

Calvert County (MD) Dragonflies and Damselflies: Part Six – Dragonfly Family Aeshnidae

Family: Aeshnidae

The Common Green Darner and the Swamp Darner are the only two species of this family that are represented for Calvert County in the iNaturalist database and that is from a single observation of each. Richard Orr’s database lists nine species from the Aeshnidae family as being present in Calvert County. St. Marys County currently has a single species (Common Green Darner) of this family in iNaturalist contrasted with seven species present in Richard Orr’s database. Charles County has three species represented in iNaturalist and Richard Orr’s database contains eight species present for the county. Consequently, much work remains to be done in order to bring the iNaturalist observations closer to the definitive database of county sightings.

Listed below are the species within the Aeshnidae family that have been observed in at least one of the southern Maryland counties and a comparison of the two databases is made (as of January, 2020). As was done with the previous family, I have included with each species a note extracted from the book “Natural History of DelMarVa Dragonflies and Damselflies” by Hal White (reference 1). Of particular relevance for Calvert County, I have also included information on the eight species of this family that were observed at the Cove Point LNG Property and reported in “2011-2012 Survey of the Dragonflies and Damseflies (Odonata) of the Cove Point LNG Property (Calvert County, Maryland” by Richard Orr (reference 2).

Shadow Darner/Aeshna umbrosa
This darner prefers a shady habitat and can feed at dusk, hence its name. (1)
Cove Point adult abundance and flight period – rare/14-Oct to 02-Dec. (2)
iNaturalist research grade observations: ​ Calvert = 0​ St. Marys = 0​​ Charles = 1 (Oct)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – X ​ Charles - present

Common Green Darner/Anax junius
This is the only species of dragonfly known from all 50 states and it has also sporadically appeared in England. (1)
Cove Point adult abundance and flight period – common/29-Mar to 14-Oct. (2)
iNaturalist research grade observations:​ Calvert = 1 (Aug) St. Marys = 1​(Sept)​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles – present

Comet Darner/Anax longipes
This darner prefers flooded sand pits and other ponds, preferably fishless, and is most often observed in June and July. (1)
Cove Point adult abundance and flight period – rare/05-Jun to 05-May. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Springtime Darner/Basiaeschna janata
As its name suggests, it can be found early in the spring patrolling steam edges. (1)
Cove Point adult abundance and flight period – rare/21-Apr to 05-May. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Fawn Darner/Boyeria vinosa
Female darners are the only dragonflies that have ovipositors that are capable of a sting. (1)
Cove Point adult abundance and flight period – rare/03-Sept. (2)
iNaturalist research grade observations: ​Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Swamp Darner/Epiaeschna heros
The females lay their eggs in wet, rotten wood in swampy areas. (1)
Cove Point adult abundance and flight period – uncommon/04-May to 17-Jul. (2)
iNaturalist research grade observations:​ Calvert = 1 (May) St. Marys = 0​ Charles = 5 (May-Aug)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Taper-tailed Darner/Gomphaeschna antilope
S2 State Rare (see below for definition)
This darner has an inclination to enter buildings and is attracted to insect light-traps. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – X​ Charles - X

Harlequin Darner/ Gomphaeschna furcillata
S3 Watch List (see below for definition)
Often lands on sunlit, vertical surfaces such as tree trunks and it will frequently mistake a human visitor for such and make a surprise landing on the individual. (1)
Cove Point adult abundance and flight period – rare/21-Apr to 24-May. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Cyrano Darner/Nasiaeschna pentacantha
S3 Watch List (see below for definition)
It is named for its prominent and distinctive nose like that of Cyrano de Bergerac of literary fame. (1)
Cove Point adult abundance and flight period – uncommon/05-May to 17-Jun. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 1 (June)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Definitions from the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”:
S2 - Imperiled / State Rare — At high risk of extinction or extirpation due to restricted range, few populations or occurrences, steep declines, severe threats, or other factors. Typically occurring in 6-20 populations.

S3 - Vulnerable / Watchlist — At moderate risk of extinction or extirpation due to a fairly restricted range, relatively few populations or occurrences, recent and widespread declines, threats, or other factors. Typically occurring in 21-80 populations.

Publicado em 09 de fevereiro de 2020, 05:11 PM por rosalie-rick rosalie-rick | 0 comentários | Deixar um comentário

08 de fevereiro de 2020

Calvert County (MD) Dragonflies & Damselflies: Part 5 - Dragonfly Family Gomphidae

Family: Gomphidae
The Ashy Clubtail is the only member of this family that is represented for Calvert County in the iNaturalist database and that is from a single observation. Richard Orr’s database has four species from the Gomphidae family listed as being present in Calvert County. The discrepancy between databases is even greater for St. Marys and Charles Counties. St. Marys County currently has zero observations in iNaturalist and six species present in Richard Orr’s database. Charles County has three species observations in iNaturalist and Richard Orr’s database contains eight species present for the county.

Listed below are the species within this family that have been observed in at least one of the southern Maryland counties and a comparison of the two databases is made (as of January, 2020). Included with each species is a note extracted from the book “Natural History of DelMarVa Dragonflies and Damselflies” by Hal White (reference 1). Also included is information on three species that were observed at the Cove Point LNG Property and reported in “2011-2012 Survey of the Dragonflies and Damseflies (Odonata) of the Cove Point LNG Property Calvert County, Maryland” by Richard Orr (reference 2)

Unicorn Clubtail/Arigomphus villosipes
The unicorn name is derived from a small horn that protrudes between the eyes. (1)
iNaturalist research grade observations: ​Calvert = 0​ St. Marys = 0​​ Charles = 2 (June)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – X ​ Charles - present

Black-shouldered Spinyleg/Dromogomphus spinosus
Dragonflies regulate their body temperature by varying their body orientation with relation to the sun. On cool days, they will perch with their body and wings perpendicular to the sun in order to maximize their exposure to the sun. On warm days they will point their abdomen towards the sun to minimize heating or move to a shady area. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – present​ Charles – X

Cobra Clubtail/Gomphurus vastus
This species has not been observed on the DelMarVa Peninsula. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – X​ Charles - present

Dragonhunter/Hagenius brevistylus
Prefers to eat large insects such as butterflies and other species of dragonflies. It is the largest clubtail dragonfly and has been called the Tyrannosaurus rex of the dragonfly world. (1)
Cove Point adult abundance and flight period – rare/16-June. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 2 (June)
MD Biodiversity (i.e., Richard Orr): ​Calvert – present St. Marys – present​ Charles - present

Lancet Clubtail/Phanogomphus exilis
Emerges on muddy banks close to the waterline and takes approximately an hour before it is able to fly. Unfortunately this makes it very susceptible to wave action from passing boats and is usually unable to recover. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 3 (May-Jun)
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – present​ Charles - present

Ashy Clubtail/Phanogomphus lividus
The largest insect ever known was Meganeura monyi, a fossilized Permian dragonfly found in France with a wingspan of over two feet. (1)
Cove Point adult abundance and flight period – uncommon/23-Apr to 04-May. (2)
iNaturalist research grade observations:​ Calvert = 1 (July) St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present ​ Charles - present

Sable Clubtail/Stenogomphurus rogersi
S2 State Rare (see below for definition)
There are only three known populations known on the DelMarVa Peninsula, two of which were only discovered since 2007. (1)
Cove Point adult abundance and flight period – rare/10-May to 14-Jun. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Eastern Least Clubtail/Stylogomphus albistylus
Research has determined that this clubtail has at least a three year life cycle with nearly all of it as aquatic nymphs. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – present​ Charles - present

Russet-tipped Clubtail/Stylurus plagiatus
S3 Watch List (see below for definition)
Most clubtails fly in spring and early summer, but this species emerges in late summer to fall. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – X​ Charles - present

Definitions from the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”:
S2 - Imperiled / State Rare — At high risk of extinction or extirpation due to restricted range, few populations or occurrences, steep declines, severe threats, or other factors. Typically occurring in 6-20 populations.

S3 - Vulnerable / Watchlist — At moderate risk of extinction or extirpation due to a fairly restricted range, relatively few populations or occurrences, recent and widespread declines, threats, or other factors. Typically occurring in 21-80 populations.

Publicado em 08 de fevereiro de 2020, 01:29 PM por rosalie-rick rosalie-rick | 0 comentários | Deixar um comentário

06 de fevereiro de 2020

Calvert County (MD) Dragonflies and Damselflies: Part Four -Dragonfly Family Petaluridae

A series of journal notes going forward will be a closer look at the various families of dragonflies and the species within that can be found in Calvert County, Maryland.

Family: Petaluridae
The following are notes from the book “Natural History of DelMarVa Dragonflies and Damselflies” by Hal White:
1) The Petaluridae family of dragonflies was the dominant group of dragonflies at the time of the dinosaurs.
2) Today, there is only one species, Gray Petaltail/Tachopteryx thoreyi, within this family in eastern North America.
3) The Gray Petaltail is one of only eleven species worldwide within this family.
4) It has only been observed on the DelMarVa peninsula once and that was over 70 years ago.

The Gray Petaltail is listed on the Maryland Department of Natural Resources (DNR) S3 watchlist. According to the DNR “List of Rare, Threatened, & Endangered Animals in Maryland, S3 has the following meaning:
S3 = Vulnerable / Watchlist — At moderate risk of extinction or extirpation due to a fairly restricted range, relatively few populations or occurrences, recent and widespread declines, threats, or other factors. Typically occurring in 21-80 populations.

Below is a comparison of two occurrence databases for the southern Maryland counties:
iNaturalist research grade observations:​ Calvert = 8​ St. Marys = 0​​ Charles = 1
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

A closer examination of the Calvert County iNaturalist observations (as of January, 2020) reveals the following:
1) Six of the eight Calvert County observations were made in Calvert Cliffs State Park (CCSP) and 4 of those 6 were made on a single day (12 June 2016) within a three hour span.
2) The other two CCSP observations were made on 02 June 2018 and 23 June 2019.
3) The remaining two Calvert County observations were made on the same day (18 June 2019); the specific location within the county not listed.
4) The date of the Charles County observation was 11 June 2019.

Moral of the story: June appears to be the month to keep an eye out for the Gray Petaltail.

Publicado em 06 de fevereiro de 2020, 06:02 PM por rosalie-rick rosalie-rick | 0 comentários | Deixar um comentário

05 de fevereiro de 2020

Calvert County (MD) Dragonflies and Damselflies: Part Three - Richard Orr & the Maryland Biodiversity Project Database

In researching dragonflies I came across a Maryland database that tracks species according to occurrence in each of the counties. Richard Orr has created a database of county records for dragonflies and damselflies in Maryland and Washington DC (see www.marylandinsects.com). He updates the database regularly and the records are also reflected in the Maryland Biodiversity Project (www.marylandbiodiversity.com). His county records are also incorporated for the Maryland Eastern Shore counties in Appendix 4&5 of the book “Natural History of DelMarVa Dragonflies and Damselflies” by Hal White. The iNaturalist database has a long way to go to catch up with county records that are consistent with Richard Orr’s records. The outstanding feature of the iNaturalist database (besides the incredible ID tools) is the ability to access individual observations that include specific locations and timepoints, invaluable aids for those wanting to observe firsthand a particular species. As more entries are made into the iNaturalist program, eventually the various databases will be consistent with one another. Until the start of D&D season is upon us in April (maybe March?), I hope to spend some time examining the occurrence of the various species in the southern Maryland counties of Calvert, Charles, and St. Marys as reflected in the databases and incorporate some of that information in upcoming posts. Once the dragonflies and damselflies emerge, hopefully I will be out photographing and adding my observations to the iNaturalist database.

Publicado em 05 de fevereiro de 2020, 08:34 PM por rosalie-rick rosalie-rick | 0 comentários | Deixar um comentário

21 de janeiro de 2020

Calvert County (MD) Dragonflies and Damselflies: Part Two – Current County Status in iNaturalist (data as of January, 2020)

The Calvert County total number of species and observations for dragonflies in iNaturalist currently stands at 26 and 328, respectively.
County damselflies are only 7 species from 76 observations.

How does these numbers compare to our other surrounding counties?
For the two Southern Maryland counties:
St. Mary’s County dragonflies - 17 species/49 observations; damselflies - 5 species/12 observations
Charles County dragonflies - 30 species/166 observations, damselflies - 9 species/23 observations
And to our north:
Anne Arundel County dragonflies – 45 species/1, 099 observations; damselflies - 27 species/286 observations

The Anne Arundel County data in particular would appear to offer the possibility that quite a few more species are waiting to be added to the iNat county database. To date, there have been a total of 68 naturalists inputting data for dragonflies and damselflies, but only seven observers have provided 10 or more observations. A new iNaturalist project for dragonflies and damselflies of Calvert County has recently (04 November 2019) been created by Karyn Molines, Chief of the Calvert County Natural Resources Division. Maybe this will inspire some others to take a closer look at these most interesting insects and input their own observations.

Publicado em 21 de janeiro de 2020, 06:45 PM por rosalie-rick rosalie-rick | 1 comentários | Deixar um comentário

20 de janeiro de 2020

Calvert County (MD) Dragonflies and Damselflies: Part One - A Nearly Invisible World Comes to Life

Prior to this past year, I am not sure that I have ever tried to photograph a dragonfly or damselfly and certainly had never tried to identify one. During a late spring hike in Calvert Cliffs State Park I happened upon a group of very large and colorful dragonflies that were periodically resting on a set of tree branches next to the trail. I took several photos with the hope that I might learn their identity using the iNaturalist app, a relatively new software program to me. Thus was the start of a season learning about a group of creatures that I knew were about, but that I knew so little about. I discovered that Rambur’s Forktail damselflies frequented the lake shore of our yard and that Blue-fronted Dancer damselflies only inhabited one side of our house. Eastern Amberwing dragonflies were generally only found resting on stumps protruding from the lake while Common Whitetail dragonflies seemed to prefer to stay on or close to our house. Flowers in the garden were often adorned with Blue Dasher or Eastern Pondhawk dragonflies. Unusual wing patterns, beautiful vibrant body colors, unusual mating positions, and a much greater variety of species were present than I could have imagined. A world that was apparently almost literally under my feet for years without any awareness on my part was now an exciting new avenue of discovery. So now in addition to trying to find and photograph the local birds, I have another incredible set of creatures to entertain me as I roam around the neighborhood and county.

Publicado em 20 de janeiro de 2020, 05:57 PM por rosalie-rick rosalie-rick | 0 comentários | Deixar um comentário