Early nesting mourning dove.

The two dead nestling mourning doves (Zenaida macroura) collected form the earliest nest on record for this species in the Kingston Region. Photo: Mark Andrew Conboy.

Mourning doves (Zenaida macroura) are among our some of the earliest breeding birds often with eggs being laid by mid to late April (Weir 2008). Doves and pigeons produce protein rich crop “milk” to feed their nestlings. The milk is produced by both sexes and may allow doves and pigeons to breed very early in the year, when resource scarcity makes it impossible for most other species to nest. Here I report an exceptionally early nesting attempt by mourning doves at QUBS.

On April 17, 2010 I found a mourning dove nest 30 m north of the intersection of the Cataraqui Trail and the Old Bedford Road. The nest was built 2.1 m above the ground in an eastern redcedar (Juniperus virginiana). The nest contained two dead nestlings. The nestlings were not warm but were still soft and blood that was on the legs of both birds and near the cloaca of one bird was still wet to the touch. I suspect that the nestlings could not have been dead for very long. One adult flushed directly from the nest so was still likely brooding and a second adult flushed from the ground about 4 m away. There was half of a morning dove eggshell on the ground immediately below the nest.
The earliest egg date for mourning dove in the Kingston region is April 14 and earliest brood date is May 13 (Weir 2008). The typical incubation period for mourning doves is 14 days (Otis et al 2008). I estimated the age of the nestlings to be about 8 days old (Hanson and Kossack 1957). Based on the estimated age of the nestlings I suggest that the first egg date for this nest would be March 27. This is 19 days earlier than the previous earliest record for the Kingston region. In the southern part of their range mourning doves may breed at any time of year (Otis et al 2008), but in Ontario breeding normally occurs during April, May and June (Peck and James 1983). The earliest egg date for mourning doves breeding in Ontario that I could locate is March 19 (Peck and James 1983). – Posted by Mark Andrew Conboy

References

• Hanson, H.C. and Kossack, C.W. 1957. Methods and criteria for aging incubated eggs and nestlings of the mourning dove. Wilson Bulletin 69: 91-101.
• Otis, D.L., Schulz, J.H., Miller, D., Mirarchi, R.E. and Baskett, T.S. 2008. Mourning dove (Zenaida macroura), In The birds of North America Online (Poole, A. editor). Cornell Lab of Ornithology.
• Peck, G.K. and James, R.D. 1983. Breeding birds of Ontario: nidiology and distribution volume 1: nonpasserines. Royal Ontario Museum.
• Weir, R.D. 2008. Birds of the Kingston region, 2nd edition. Kingston Field Naturalists.

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Two new dragonfly species for QUBS

Swamp darner (Epiaeschna heros). Though the thorax is shaded the diagnostic narrow green abdominal markings are clearly visible on this, our largest darner species. Photo: Kurt Hennige.

Although the 2010 dragonfly flight season has not yet begun, we already have two new rare species to add to the station checklist. Digging around in some old documents I turned up one record of a swamp darner (Epiaeschna heros) on July 15, 1975 along Queen’s University Road and one record of a stygian shadowdragon (Neurocordulia yamaskanensis) at Hart Lake on Aug 17, 2004 (Catling et al. 2005). These are to my knowledge the first records of these rare species at QUBS. Both of species were listed as hypothetical (i.e. not yet recorded at QUBS but expected to be found) on the new dragonfly checklist (Smith et al. 2009). The new statuses that will appear in an updated version of the checklist will be Rare for swamp darner and Rare and Local for stygian shadowdragon.

The swamp darner record is an old one and no observer names are given. Catling et al (2005) report that there was a specimen in the QUBS collection, but that specimen appears to have been lost. Queen’s University Road, where the specimen was collected, has proven to be a good location for finding rare dragonflies. Two harlequin darners (Gomphaeschna furcillata) were discovered there in 2009 (MAC) and a Cyrano darner (Nasiaeschna pentacantha) was captured some years ago (Floyd Connor, pers. comm.).

Stygian shadowdragon is a crepuscular species that always seems to be under reported wherever it is found. That being said it appears to be genuinely rare at QUBS. The single record for stygian shadowdragon at QUBS was a single exuvium found by Paul Catling and Brenda Kostiuk. They discovered a single exuvium near a creek that flows into Hart Lake. Apparently this exuvium is now a voucher specimen in the Canadian National Collection (Catling et al. 2005).

Not only are both of these species rare at QUBS, but they are regionally rare too. Kurt Hennige of the Kingston Field Naturalists says that swamp darners are seldom reported in the Kingston region. There have been four records near Outlet (Charleston Lake area). As for stygian shadowdragon, David Bree (Ontario Parks) caught two in June 2008 at Elbow Lake. Apparently this was the first record of this species for the area (Hennige, pers. comm.). The record in Cartling et al (2005) precedes it by four years.

It is exciting to add such uncommon species to the QUBS list. Perhaps more interesting records will turn up as we find the time to sort through old documentation. An updated dragonfly checklist for QUBS will be posted on the website later this spring. – Posted by Mark Andrew Conboy

References
Catling, P.M., Kostiuk, B. and Connor, F. 2005. Odonata collected in the vicinity of the Queen’s University Biology [sic] Station at Chaffey’s Lock. Ontario Odonata 6. Toronto Entomologists Association.
Smith, B. Muma, K., Conboy, M.A and Connor, Floyd. 2009. Dragonflies of Queen’s University Biological Station.