Henslow's sparrow (Ammodramus henslowii): residence description

Section 33 of the Species at Risk Act (SARA) prohibits damaging or destroying the residence of a listed threatened, endangered, or extirpated species. SARA defines residence as: “a dwelling-place, such as a den, nest or other similar area or place, that is occupied or habitually occupied by one or more individuals during all or part of their life cycles, including breeding, rearing, staging, wintering, feeding or hibernating” [s.2(1)]. With respect to a listed wildlife species that is an aquatic species or a species of bird protected under the Migratory Birds Convention Act, 1994, the prohibition applies wherever residence of the species is found. For any other listed wildlife species, the prohibition applies automatically when the residence of the species is on federal lands and will only apply on non-federal lands if an order is made pursuant to sections 34 or 35 of SARA. Under section 97 of SARA every person who contravenes section 33 of the Act commits an offence.

The following is a description of residence for the Henslow’s sparrow (Ammodramus henslowii), created for the purposes of increasing public awareness and aiding enforcement of the above prohibition. Henslow’s sparrows are known to have one type of residence -- the nest.

Species information

Scientific name

Ammodramus henslowii

Common name

Henslow's sparrow

Current COSEWIC status & year of designation

Endangered 2000

Range in Canada

Ontario (no map available)

Rationale for status

This species has disappeared from most of its former limited range in Canada. Birds were only documented at nine locations in the 2001-2005 Ontario Breeding Bird Atlas. Habitat loss and degradation have largely induced the population decline.

1 The nest

Physical appearance and context

Henslow’s sparrows nest in tall grass prairie communities and agricultural areas such as abandoned fields, ungrazed or lightly grazed pasture, fallow hayfields with high clover and alfalfa content, grassy swales in open rolling farmland, wet meadows, and infrequently mowed fields^Footnote1. Their preferred nesting habitat can be characterized as relatively large fields (>30 ha) with tall (approx 0.5 m) dense grass, a well developed litter layer, standing dead vegetation, and sparse woody vegetation^Footnote1,^Footnote2,^Footnote3. Such areas are usually characterized by a high percentage of grasses and scattered forbs, a thick mat of ground cover from previous years’ vegetation, and no current disturbance in the form of grazing livestock^Footnote2. Nests, typically constructed out of dead vegetation, are well hidden at the base of grass clumps in areas of thick litter, and are not fastened to standing vegetation^Footnote1,^Footnote2. Lined with hair, the nest is partially domed over with surrounding grasses^Footnote4. The bottom of the cup-shaped nest ranges from one to several cm above ground ^Footnote1,^Footnote2.

Function

The nest provides a container in which adult Henslow’s sparrows lay and incubate eggs, and rear hatchlings. The adult female builds the nest (4-6 days)^Footnote1,^Footnote2, and lays one egg per day (clutch size is 3-5 eggs). Eggs are creamy white or pale greenish white in colour with speckles, spots, or large blotches of reddish brown or gray concentrated at the larger end, often forming a wreath^Footnote2. The adult female incubates eggs for 10-11 days and broods hatchlings for 4-5 days; both parents feed nestlings^Footnote2. Young leave the nest site at 9-10 days^Footnote2.

Damage/destruction of residence

Any activity that moves or otherwise disturbs the eggs or nest, changes the microclimate of the nest, or blocks access to the nest could result in damage or destruction of the residence. Agricultural activities that disturb ground vegetation such as grazing, burning, ploughing, tilling, or chemical spraying may damage or destroy the residence if performed during the nesting period.

Period and frequency of occupancy

Henslow’s sparrows return to Canadian breeding grounds in late April to early May, with nest building commencing shortly thereafter^Footnote1. It is unknown if this species double broods in Ontario, but they will renest if the first nest attempt fails^Footnote1, so nesting activity could continue into late August. Birds will nest in the same area as in previous years, often close to the previous year’s nest^Footnote2. The nest site should be protected as a residence from late April until the end of August.

Additional information

For more information on the Henslow’s Sparrow, please visit the species' profile.

For more information on SARA, please visit the SAR Registry.

Recommended citation

Please cite this document as:

Government of Canada. Species at Risk Act Public Registry. Residence Descriptions. Description of residence for Henslow’s Sparrow (Ammodramus henslowii) in Canada. December 2006.