2025 South Middleton Township Bird Town PA Cavity Nest Program

Species Totals – 2025 CV Cavity Nest Program

Species	# Records Logged	Total Eggs (max counts)	Total Young (max counts)	Total Fledged	Notes
Eastern Bluebird	95	205	159	113	Core species; multiple broods, but many nests with 0 fledged despite eggs/young present
Tree Swallow	55	126	109	93	Strong occupancy: several nests with 4–6 fledged successfully
Carolina Chickadee	15	69	65	55	Mixed outcomes: some nests failed completely
House Sparrow	12	20 eggs (often left)	N/A	N/A	Invasive competitor: eggs often abandoned or removed
House Wren	10	82	65	55	Productive late‑season nests, some full broods fledged
Purple Martin	5	15	15	15	Limited but promising presence

Eastern Bluebird (95 records, 205 eggs, 113 fledged)

Core species, but fledging success was uneven.
Pattern: multiple broods possible, yet many nests produced zero fledglings despite eggs/young present.
- Environmental Stressor: The main decline from last year’s overall fledgling count was linked to long periods of excessive heat, which likely contributed to nest failures and uneven productivity across species.

Tree Swallow (55 records, 126 eggs, 93 fledged)

Carolina Chickadee (15 records, 69 eggs, 55 fledged)

Mixed outcomes: some nests are highly productive; others are complete failures.
Environmental Stressor: The main decline compared to last year’s overall fledgling count was linked to prolonged periods of excessive heat, which contributed to nest failures and uneven productivity across species.

House Sparrow (12 records, 20 eggs, no fledged)

Consistent management issue.
Eggs are often abandoned or removed, confirming their role as a non-productive competitor.

House Wren (10 records, 82 eggs, 55 fledged)

Purple Martin (5 records, 15 eggs, 15 fledged)

Purple Martin Expansion: Explore adding more martin housing to encourage colony growth.
Volunteer Engagement: Share species-specific success stories to highlight program impact.

Program-Wide Observations

Efficiency Leaders: Tree Swallows and Purple Martins demonstrated the best egg-to-fledge conversion.
Core Species Variability: Eastern Bluebirds dominated in numbers but underperformed in consistency.
Management Challenge: House Sparrows remain a drain on box availability and require active intervention.
Seasonal Boost: House Wrens extended productivity into the late season, stabilizing totals.
Biodiversity Value: Even small numbers of Purple Martins add ecological and outreach value.

Next-Step Considerations

Bluebird Nest Failures: What else can be done to combat heat stress?
Sparrow Control: Move boxes farther away from populated areas.
Habitat Optimization: Compare high success vs. failed sites for microhabitat differences.
House Sparrows were a recurring management issue, with eggs left in boxes but no productive broods.
House Wrens contributed meaningful late‑season productivity.
Purple Martins appeared in small numbers but are a valuable addition to the species mix.

Andrew Dapkins

Bird Town PA

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