Landscape of Change Results

Have Changes Occurred Between 1880 and Now?

Birds

Introduction

In the 1880s, a group of Harvard students known as the Champlain Society spent summers on Mount Desert Island (MDI) conducting surveys of flora and fauna, including birds. Their records, preserved by the Mount Desert Island Historical Society, present an opportunity to evaluate changes in bird populations on the island, which is now home to Acadia National Park. North America has lost nearly 3 billion birds in recent times. According to Rosenberg et al. (2019), this is a loss of 25% of all birds on the continent since 1970! This shocking decline in North America’s bird population is an important reason why it’s so critical to study bird populations locally.

This study’s objective was to compare the Champlain Society’s records to the past 4 years of eBird and iNaturalist data for Mount Desert Island. Our goals were to determine: 1) how historically recorded species’ relative abundance changed over the last 140 years, 2) if new species are present on the island, and 3) what we hypothesize caused these changes in MDI bird populations.

Methods

The historical data from the Champlain Society were collected from early July through the first week of September 1880 – 1883. To compare these data to modern day, we used eBird and iNaturalist data filtered to the same time frame (early July through the first week of September), and over the same number of years from 2018 – 2021. To compare how often these species were/are detected, we had to create a qualitative descriptor properly assigned to the species as the historical dataset did not allow for a quantitative analysis. These designations are found in the Champlain Society’s notes (Spelman 1941), are based on their own observations and experiences, and follow the convention of other national and regional bird lists of the period. For the modern dataset, we used a count of the number of times a species was reported and designated a category based on these bins: < 5 = very rare, 5 > 20 = rare, 20 > 50 = uncommon, > 50 = common. These standards are adapted from the American Birding Association (2022).

We used these relative abundances to compare modern and historic times. Due to the qualitative nature of the data, we designated species with changes of more than one category into the “increasing” or “decreasing” tables. So, if a species was “common” in the 1880s but is now “uncommon”, that would not constitute a decrease that we can be confident in. Whereas, if a species was “common” in the 1880s but is now “rare”, that would qualify as a decreasing species because we are confident that a change of that magnitude is real. For example, Cliff Swallow was a historically “common” species but now is “very rare” on MDI, and therefore is decreasing. In contrast, Sharp-shinned Hawk was “uncommon” historically and is now “common”, but this difference is not enough to determine if it is increasing and is therefore categorized as “no change.”

Results

The Champlain Society recorded 98 species, which is less than half (47%) of the 210 species recorded in modern times according to eBird and iNaturalist. The Champlain Society categorized 60 species as common, while today there are 95. This is an increase of 35 common species over 140 years.

When we examined the changes in relative abundance of historically observed bird species over the last 140 years, we found that 8% of these species increased in relative abundance (Table 1), 14% decreased (Table 2), and 76% exhibited no change (Figure 1). Table 1 also includes more notably increasing species that were not detected by the Champlain Society, but are now uncommon or common on MDI. Some examples of the 8% of historic species that have increased are Black-throated Blue Warbler (Figure 2), Blue Jay (Figure 3), and Eastern Phoebe (Figure 4). Examples of the 14% of historic species that have decreased are American Woodcock (Figure 5), Black-crowned Night-Heron (Figure 6), and Yellow-bellied Flycatcher (Figure 7).

Modern day records show 82 species not recorded by the Champlain Society, that are regularly documented by observers today (Table 3). Three of these species were introduced by humans between the 1880s and present day: House Sparrow, European Starling, and Rock Pigeon. For a complete list of relative abundance changes by species see Table 4.

Conclusion and Next Steps

Of the species recorded by the Champlain Society that have increased in relative abundance, most can be explained by human-caused changes to the landscape. For example, human urbanization of natural landscapes is proposed to be the main reason for Blue Jay range expansion (Smith et al. 2020). Similar reasoning can be attributed to the Eastern Phoebe increase that we have seen. As modern infrastructure developed, bridges and structures have become more prominent, which has been linked to the range expansion of this species (Weeks Jr. 2020). Another cause for some of these species’ local increases can be associated with European colonization. Black-throated Blue Warbler was likely driven out of MDI due to the extensive logging and associated changes to the forest leaving MDI with little appropriate habitat (Irland 1982). In more recent times forested ecosystems have regenerated allowing for Black-throated Blue Warbler to return to the region (Holmes et al. 2020).

Similar changes in the landscape might explain those species that have decreased in relative abundance. For example, the American Woodcock has decreased due to the transition of farmlands to forest (McAuley 2020), while the Black-crowned Night-Heron decrease has been attributed to the loss of wetland habitats (Hothem et al. 2020). Additionally, species that breed in boreal landscapes such as Pine Siskin and Yellow-bellied Flycatcher show local declines due to boreal habitats disappearing from climate warming, habitat degradation, and logging (Price et al. 2013).

We also wanted to look more closely at the species present on MDI today, but not recorded historically by the Champlain Society’s efforts. These species are those whose ranges may have expanded or shifted north due to climate change or other factors, and those that can be attributed to human-caused changes on the landscape. This trend of climate changes and human manipulation of the landscape have had dramatic effects on the birds of MDI, but the effects are often species-specific and highly variable. Future research to explain the changes we saw might incorporate additional data sets, such as the Audubon Christmas Bird Count and Maine Breeding Bird Atlas, as well as analyze changes in Mount Desert Island habitat types and land cover.

Species Changes

Figure 1. This figure shows the number of bird species recorded by the Champlain Society in the 1880s that have increased, decreased, and showed no change in relative abundance from the 1880’s to present day. Data collected on Mount Desert Island, Maine, USA, and provided by eBird and iNaturalist.

Increasing Species

Table 1. This table shows the species recorded by the Champlain Society with notable increases in relative abundance. Also included are species with intensive increases in relative abundance that were not recorded in the 1880s by the Champlain Society. There are 33 species that are now common on MDI, and 19 uncommon species that were not present historically. Data collected on Mount Desert Island, Maine, USA, and provided by eBird and iNaturalist.

Click to show table

‘R. a.’ = Relative abundance

Common name	Scientific name	R. a. 1880’s	R. a. modern	R. a. changes
Black-throated Blue Warbler	Setophaga caerulescens	very rare	common	increased
Blue Jay	Cyanocitta cristata	rare	common	increased
Brown Creeper	Certhia americana	rare	common	increased
Eastern Bluebird	Sialia sialis	very rare	uncommon	increased
Eastern Phoebe	Sayornis phoebe	rare	common	increased
Red Crossbill	Loxia curvirostra	rare	common	increased
Red-tailed Hawk	Buteo jamaicensis	very rare	uncommon	increased
Solitary Sandpiper	Tringa solitaria	rare	common	increased
Black-bellied Plover	Pluvialis squatarola	not detected	uncommon	increased
Blackpoll Warbler	Setophaga striata	not detected	uncommon	increased
Canada Goose	Branta canadensis	not detected	common	increased
Cape May Warbler	Setophaga tigrina	not detected	uncommon	increased
Common Eider	Somateria mollissima	not detected	common	increased
Common Grackle	Quiscalus quiscula	not detected	common	increased
Common Merganser	Mergus merganser	not detected	common	increased
Common Raven	Corvus corax	not detected	common	increased
Cooper’s Hawk	Accipiter cooperii	not detected	uncommon	increased
Double-crested Cormorant	Nannopterum auritum	not detected	common	increased
Eastern Towhee	Pipilo erythrophthalmus	not detected	common	increased
Eastern Wood-Pewee	Contopus virens	not detected	common	increased
European Starling	Sturnus vulgaris	not detected	uncommon	increased
Gray Catbird	Dumetella carolinensis	not detected	common	increased
Great Black-backed Gull	Larus marinus	not detected	common	increased
Great Cormorant	Phalacrocorax carbo	not detected	uncommon	increased
Great Crested Flycatcher	Myiarchus crinitus	not detected	uncommon	increased
Great Egret	Ardea alba	not detected	uncommon	increased
Green-winged Teal	Anas crecca	not detected	uncommon	increased
Hooded Merganser	Lophodytes cucullatus	not detected	common	increased
House Finch	Haemorhous mexicanus	not detected	common	increased
House Sparrow	Passer domesticus	not detected	common	increased
Laughing Gull	Leucophaeus atricilla	not detected	common	increased
Least Flycatcher	Empidonax minimus	not detected	uncommon	increased
Mallard	Anas platyrhynchos	not detected	common	increased
Merlin	Falco columbarius	not detected	common	increased
Mourning Dove	Zenaida macroura	not detected	common	increased
Nelson’s Sparrow	Ammospiza nelsoni	not detected	common	increased
Northern Cardinal	Cardinalis cardinalis	not detected	common	increased
Northern Gannet	Morus bassanus	not detected	common	increased
Palm Warbler	Setophaga palmarum	not detected	uncommon	increased
Peregrine Falcon	Falco peregrinus	not detected	common	increased
Pileated Woodpecker	Dryocopus pileatus	not detected	common	increased
Pine Warbler	Setophaga pinus	not detected	common	increased
Red-necked Grebe	Podiceps grisegena	not detected	uncommon	increased
Ring-billed Gull	Larus delawarensis	not detected	common	increased
Rock Pigeon	Columba livia	not detected	common	increased
Ruby-crowned Kinglet	Corthylio calendula	not detected	uncommon	increased
Semipalmated Plover	Charadrius semipalmatus	not detected	common	increased
Snowy Egret	Egretta thula	not detected	uncommon	increased
Swamp Sparrow	Melospiza georgiana	not detected	common	increased
Tennessee Warbler	Leiothlypis peregrina	not detected	uncommon	increased
Tufted Titmouse	Baeolophus bicolor	not detected	uncommon	increased
Turkey Vulture	Cathartes aura	not detected	common	increased
Veery	Catharus fuscescens	not detected	uncommon	increased
White-breasted Nuthatch	Sitta carolinensis	not detected	common	increased
White-winged Scoter	Melanitta deglandi	not detected	common	increased
Wild Turkey	Meleagris gallopavo	not detected	common	increased
Wilson’s Storm-Petrel	Oceanites oceanicus	not detected	uncommon	increased
Wood Duck	Aix sponsa	not detected	common	increased
Wood Thrush	Hylocichla mustelina	not detected	common	increased
Yellow-bellied Sapsucker	Sphyrapicus varius	not detected	uncommon	increased

Figure 2. Black-throated Blue Warbler (Setophaga caerulescens) modern day distribution across MDI. Data provided by eBird and iNaturalist, 2018 - 2021.

Figure 3. Blue Jay (Cyanocitta cristata) modern day distribution across MDI. Data provided by eBird and iNaturalist, 2018 - 2021.

Figure 4. Eastern Phoebe (Sayornis phoebe) modern day distribution across MDI. Data provided by eBird and iNaturalist, 2018 - 2021.

Decreasing Species

Table 2. This table shows the species that exhibited notable decreases in relative abundance since the 1880s. Data collected on Mount Desert Island, Maine, USA, and provided by eBird and iNaturalist.

Click to show table

‘R. a.’ = Relative abundance

Common name	Scientific name	R. a. 1880’s	R. a. modern	R. a. changes
American Woodcock	Scolopax minor	common	rare	decreased
Bank Swallow	Riparia riparia	common	rare	decreased
Black-billed Cuckoo	Coccyzus erythropthalmus	common	rare	decreased
Black-crowned Night-Heron	Nycticorax nycticorax	common	very rare	decreased
Black-legged Kittiwake	Rissa tridactyla	uncommon	very rare	decreased
Canada Warbler	Cardellina canadensis	common	rare	decreased
Chimney Swift	Chaetura pelagica	common	rare	decreased
Cliff Swallow	Petrochelidon pyrrhonota	common	very rare	decreased
Passenger Pigeon	Ectopistes migratorius	rare	extinct	decreased
Pine Siskin	Spinus pinus	common	rare	decreased
Ruffed Grouse	Bonasa umbellus	common	rare	decreased
Yellow-bellied Flycatcher	Empidonax flaviventris	common	rare	decreased

Figure 5. American Woodcock (Scolopax minor) modern day distribution across MDI. Data provided by eBird and iNaturalist, 2018 - 2021.

Figure 6. Black-crowned Night-Heron (Nycticorax nycticorax) modern day distribution across MDI. Data provided by eBird and iNaturalist, 2018 - 2021.

Figure 7. Yellow-bellied Flycatcher (Empidonax flaviventris) modern day distribution across MDI. Data provided by eBird and iNaturalist, 2018 - 2021.

Modern Species not Recorded Historically

Table 3. This table shows the species that can be seen regularly (those with the relative frequencies of rare, uncommon, and common) on MDI, but were not documented in the 1880s by the Champlain Society’s efforts.

Click to show table

Common name	Scientific name	Relative abundance
American Kestrel	Falco sparverius	rare
American Oystercatcher	Haematopus palliatus	rare
Arctic Tern	Sterna paradisaea	rare
Atlantic Puffin	Fratercula arctica	rare
Baltimore Oriole	Icterus galbula	rare
Black-bellied Plover	Pluvialis squatarola	uncommon
Blackpoll Warbler	Setophaga striata	uncommon
Brown-headed Cowbird	Molothrus ater	rare
Canada Goose	Branta canadensis	common
Cape May Warbler	Setophaga tigrina	uncommon
Carolina Wren	Thryothorus ludovicianus	rare
Common Eider	Somateria mollissima	common
Common Grackle	Quiscalus quiscula	common
Common Merganser	Mergus merganser	common
Common Murre	Uria aalge	rare
Common Raven	Corvus corax	common
Cooper’s Hawk	Accipiter cooperii	uncommon
Double-crested Cormorant	Nannopterum auritum	common
Eastern Towhee	Pipilo erythrophthalmus	common
Eastern Wood-Pewee	Contopus virens	common
European Starling	Sturnus vulgaris	uncommon
Field Sparrow	Spizella pusilla	rare
Gray Catbird	Dumetella carolinensis	common
Great Black-backed Gull	Larus marinus	common
Great Cormorant	Phalacrocorax carbo	uncommon
Great Crested Flycatcher	Myiarchus crinitus	uncommon
Great Egret	Ardea alba	uncommon
Great Shearwater	Ardenna gravis	rare
Green-winged Teal	Anas crecca	uncommon
Hooded Merganser	Lophodytes cucullatus	common
House Finch	Haemorhous mexicanus	common
House Sparrow	Passer domesticus	common
House Wren	Troglodytes aedon	rare
Killdeer	Charadrius vociferus	rare
Laughing Gull	Leucophaeus atricilla	common
Least Flycatcher	Empidonax minimus	uncommon
Lesser Black-backed Gull	Larus fuscus	rare
Lincoln’s Sparrow	Melospiza lincolnii	rare
Mallard	Anas platyrhynchos	common
Merlin	Falco columbarius	common
Mourning Dove	Zenaida macroura	common
Nelson’s Sparrow	Ammospiza nelsoni	common
Northern Cardinal	Cardinalis cardinalis	common
Northern Gannet	Morus bassanus	common
Northern Goshawk	Accipiter gentilis	rare
Northern Mockingbird	Mimus polyglottos	rare
Olive-sided Flycatcher	Contopus cooperi	rare
Palm Warbler	Setophaga palmarum	uncommon
Peregrine Falcon	Falco peregrinus	common
Philadelphia Vireo	Vireo philadelphicus	rare
Pileated Woodpecker	Dryocopus pileatus	common
Pine Warbler	Setophaga pinus	common
Razorbill	Alca torda	rare
Red-breasted Merganser	Mergus serrator	rare
Red-necked Grebe	Podiceps grisegena	uncommon
Red-necked Phalarope	Phalaropus lobatus	rare
Red-shouldered Hawk	Buteo lineatus	rare
Ring-billed Gull	Larus delawarensis	common
Rock Pigeon	Columba livia	common
Rose-breasted Grosbeak	Pheucticus ludovicianus	rare
Ruby-crowned Kinglet	Corthylio calendula	uncommon
Sanderling	Calidris alba	rare
Scarlet Tanager	Piranga olivacea	rare
Semipalmated Plover	Charadrius semipalmatus	common
Snowy Egret	Egretta thula	uncommon
Surf Scoter	Melanitta perspicillata	rare
Swamp Sparrow	Melospiza georgiana	common
Tennessee Warbler	Leiothlypis peregrina	uncommon
Tufted Titmouse	Baeolophus bicolor	uncommon
Turkey Vulture	Cathartes aura	common
Veery	Catharus fuscescens	uncommon
Warbling Vireo	Vireo gilvus	rare
Whimbrel	Numenius phaeopus	rare
White-breasted Nuthatch	Sitta carolinensis	common
White-rumped Sandpiper	Calidris fuscicollis	rare
White-winged Scoter	Melanitta deglandi	common
Wild Turkey	Meleagris gallopavo	common
Wilson’s Storm-Petrel	Oceanites oceanicus	uncommon
Wood Duck	Aix sponsa	common
Wood Thrush	Hylocichla mustelina	common
Yellow-bellied Sapsucker	Sphyrapicus varius	uncommon
Yellow-billed Cuckoo	Coccyzus americanus	rare

Total Species List Changes

Table 4. This table depicts the species recorded by the Champlain Society with their relative abundance status from the 1880s contrasted with today’s. Data collected on Mount Desert Island, Maine, USA, and provided by eBird and iNaturalist.

Click to show table

‘R. a.’ = Relative abundance

Common name	Scientific name	R. a. 1880’s	R. a. modern
Alder Flycatcher	Empidonax alnorum	common	common
American Bittern	Botaurus lentiginosus	rare	uncommon
American Black Duck	Anas rubripes	common	common
American Crow	Corvus brachyrhynchos	common	common
American Goldfinch	Spinus tristis	common	common
American Redstart	Setophaga ruticilla	common	common
American Robin	Turdus migratorius	common	common
American Woodcock	Scolopax minor	common	rare
Bald Eagle	Haliaeetus leucocephalus	common	common
Bank Swallow	Riparia riparia	common	rare
Barn Swallow	Hirundo rustica	common	common
Barred Owl	Strix varia	uncommon	common
Bay-breasted Warbler	Setophaga castanea	common	uncommon
Belted Kingfisher	Megaceryle alcyon	common	common
Black Guillemot	Cepphus grylle	common	common
Black Scoter	Melanitta americana	rare	uncommon
Black-and-white Warbler	Mniotilta varia	common	common
Black-billed Cuckoo	Coccyzus erythropthalmus	common	rare
Black-capped Chickadee	Poecile atricapillus	common	common
Black-crowned Night-Heron	Nycticorax nycticorax	common	very rare
Black-legged Kittiwake	Rissa tridactyla	uncommon	very rare
Black-throated Blue Warbler	Setophaga caerulescens	very rare	common
Black-throated Green Warbler	Setophaga virens	common	common
Blackburnian Warbler	Setophaga fusca	common	common
Blue Jay	Cyanocitta cristata	rare	common
Blue-headed Vireo	Vireo solitarius	common	common
Bobolink	Dolichonyx oryzivorus	uncommon	uncommon
Bonaparte’s Gull	Chroicocephalus philadelphia	uncommon	common
Boreal Chickadee	Poecile hudsonicus	rare	very rare
Broad-winged Hawk	Buteo platypterus	common	common
Brown Creeper	Certhia americana	rare	common
Canada Warbler	Cardellina canadensis	common	rare
Cedar Waxwing	Bombycilla cedrorum	common	common
Chestnut-sided Warbler	Setophaga pensylvanica	common	common
Chimney Swift	Chaetura pelagica	common	rare
Chipping Sparrow	Spizella passerina	common	common
Common Loon	Gavia immer	uncommon	common
Common Nighthawk	Chordeiles minor	common	common
Common Tern	Sterna hirundo	common	common
Common Yellowthroat	Geothlypis trichas	common	common
Dark-eyed Junco	Junco hyemalis	common	common
Downy Woodpecker	Dryobates pubescens	common	common
Eastern Bluebird	Sialia sialis	very rare	uncommon
Eastern Kingbird	Tyrannus tyrannus	uncommon	rare
Eastern Phoebe	Sayornis phoebe	rare	common
Golden-crowned Kinglet	Regulus satrapa	common	common
Great Blue Heron	Ardea herodias	common	common
Greater Yellowlegs	Tringa melanoleuca	uncommon	common
Hairy Woodpecker	Dryobates villosus	common	common
Hermit Thrush	Catharus guttatus	common	common
Herring Gull	Larus argentatus	common	common
Indigo Bunting	Passerina cyanea	rare	very rare
Leach’s Storm-Petrel	Hydrobates leucorhous	rare	rare
Least Sandpiper	Calidris minutilla	common	common
Lesser Yellowlegs	Tringa flavipes	uncommon	common
Long-tailed Duck	Clangula hyemalis	very rare	very rare
Magnolia Warbler	Setophaga magnolia	common	common
Nashville Warbler	Leiothlypis ruficapilla	common	uncommon
Northern Flicker	Colaptes auratus	common	common
Northern Harrier	Circus hudsonius	rare	uncommon
Northern Parula	Setophaga americana	common	common
Northern Waterthrush	Parkesia noveboracensis	rare	rare
Osprey	Pandion haliaetus	common	common
Ovenbird	Seiurus aurocapilla	common	common
Pectoral Sandpiper	Calidris melanotos	very rare	very rare
Pied-billed Grebe	Podilymbus podiceps	rare	very rare
Pine Siskin	Spinus pinus	common	rare
Purple Finch	Haemorhous purpureus	common	common
Red Crossbill	Loxia curvirostra	rare	common
Red-breasted Nuthatch	Sitta canadensis	common	common
Red-eyed Vireo	Vireo olivaceus	common	common
Red-tailed Hawk	Buteo jamaicensis	very rare	uncommon
Red-winged Blackbird	Agelaius phoeniceus	uncommon	common
Ring-necked Duck	Aythya collaris	rare	very rare
Ruby-throated Hummingbird	Archilochus colubris	common	common
Ruddy Turnstone	Arenaria interpres	uncommon	rare
Ruffed Grouse	Bonasa umbellus	common	rare
Savannah Sparrow	Passerculus sandwichensis	common	common
Semipalmated Sandpiper	Calidris pusilla	common	common
Sharp-shinned Hawk	Accipiter striatus	uncommon	common
Short-billed Dowitcher	Limnodromus griseus	uncommon	rare
Solitary Sandpiper	Tringa solitaria	rare	common
Song Sparrow	Melospiza melodia	common	common
Spotted Sandpiper	Actitis macularius	common	common
Swainson’s Thrush	Catharus ustulatus	common	common
Tree Swallow	Tachycineta bicolor	common	common
Vesper Sparrow	Pooecetes gramineus	rare	rare
White-throated Sparrow	Zonotrichia albicollis	common	common
White-winged Crossbill	Loxia leucoptera	rare	uncommon
Wilson’s Warbler	Cardellina pusilla	rare	rare
Winter Wren	Troglodytes hiemalis	common	common
Yellow Warbler	Setophaga petechia	common	common
Yellow-bellied Flycatcher	Empidonax flaviventris	common	rare
Yellow-rumped Warbler	Setophaga coronata	common	common
Eastern Whip-poor-will	Antrostomus vociferus	rare	very rare
Passenger Pigeon	Ectopistes migratorius	rare	extinct
Cliff Swallow	Petrochelidon pyrrhonota	common	very rare
Purple Martin	Progne subis	rare	very rare

References

American Birding Association (2022). ABA Checklist; Checklist Codes. https://www.aba.org/aba-checklist/

Holmes, R. T., S. A. Kaiser, N. L. Rodenhouse, T. S. Sillett, M. S. Webster, P. Pyle, and M. A. Patten (2020). Black-throated Blue Warbler (Setophaga caerulescens), version 1.0. In Birds of the World (P. G. Rodewald, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.btbwar.01

Hothem, R. L., B. E. Brussee, W. E. Davis Jr., A. Martínez-Vilalta, A. Motis, and G. M. Kirwan (2020). Black-crowned Night-Heron (Nycticorax nycticorax), version 1.0. In Birds of the World (S. M. Billerman, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.bcnher.01

Irland, L. C. (1982). Wildlands and woodlots: the story of New England’s forests. Hanover, NH: Univ. Press of New England.

McAuley, D. G., D. M. Keppie, and R. M. Whiting Jr. (2020). American Woodcock (Scolopax minor), version 1.0. In Birds of the World (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.amewoo.01

Price, D.T., R.I. Alfaro, K.J. Brown, M.D. Flannigan, R.A. Fleming, E.H. Hogg, et al. (2013). Anticipating the consequences of climate change for Canada’s boreal forest ecosystems. Environ. Rev., 21, pp. 322-365

Rosenberg, K.V., Dokter, A.M., Blancher, P.J., Sauer, J.R., Smith, A.C., Smith, P.A., Stanton, J.C., Panjabi, A., Helft, L., Parr, M., Marra, P.P. (2019). Decline of the North American avifauna. Science 366, 120–124.

Smith, K. G., K. A. Tarvin, and G. E. Woolfenden (2020). Blue Jay (Cyanocitta cristata), version 1.0. In Birds of the World (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.blujay.01

Spelman, H. M. (1941). A list of the birds observed by the ornithological department of the Champlain Society during the summers of 1880-1-2-3. Unpublished manuscript in Acadia National Park archives.

Weeks Jr., H. P. (2020). Eastern Phoebe (Sayornis phoebe), version 1.0. In Birds of the World (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.easpho.01

Insects

Introduction

In the early 1900s, William Procter, a biologist associated with the Mount Desert Island Biological Laboratory, inventoried the insects of MDI over 30 field seasons. These records have been preserved by Acadia National Park archives, and were published in Volume 7 of the Biological Survey of the Mount Desert Region (1946). This, in a similar fashion to the Champlain Society’s bird records, allowed for an opportunity to evaluate changes of insect diversity in and around Acadia National Park.

We focused on two groups of insects that are generally known as pollinators: Butterflies (order Lepidoptera), and Bees (family Apidae). Pollination is a critical ecosystem service performed by animals that 75% of the world’s plants rely on to reproduce (Natural Resource Council, 2007). This includes species of fruits, vegetables, and other plants that we rely upon for food, drugs, and oxygen (USDA 2021). However, these species are facing many threats such as parasites, pathogens, pesticides and environmental stressors that are causing major die-off of many pollinating insects (USDA 2021).

This study’s objective was to examine how the local Lepidoptera and Apidae insects have changed between the early 1900’s and present day. Our goals were to determine: 1) how well did Landscape of Change’s citizen science efforts do in engaging the public to survey insects on MDI, 2) what species are no longer present that were recorded 100 years ago, and 3) what species are present today that were not recorded by Procter.

Methods

Landscape of Change focuses broadly on two groups of insects that include pollinating species: family Apidae and order Lepidoptera. While the Landscape of Change citizen science project took place in 2021, a broader effort to crowdsource biodiversity data of the Downeast and Acadia Region using iNaturalist has been ongoing since 2012. To determine how well these efforts did in engaging citizen scientists to record these insects, we compared the number of species on MDI identified to species by the iNaturalist community 2012 - 2021, and compared this to a historical collection of insects compiled by Procter in the early 1900s (1927 - 1950 with a few earlier records). We used only iNaturalist records that were identified to species and labeled as Research Grade. We then compared these two data sets to examine species not recorded 100 years ago, and specific changes in threatened or endangered species.

Acadia National Park has archives of all specimens collected in and around the park from historic times to modern day. This includes specimens from more intensive scientific surveys such as the Maine Bumble Bee Atlas, and bio-blitzes. We used this expanded dataset of bumble bees to get a better representation of insect changes in the region.

Results

Between Lepidoptera and Apidae, Procter had collected 1,360 species, while the iNaturalist community over the last 10 years identified 362 species. The iNaturalist community identified 20% (n = 274) of the 1,360 species that Procter documented in the 1900s. This means there were 88 species identified by the iNaturalist community that were not recorded by Procter’s efforts, and were likely not present in the early 1900s (Table 1). For a full look at the species diversity between all families, see Figure 1.

We examined the bumble bees (Bombus spp.) to represent a group of pollinating insects. There were 10 species recorded by Procter, and 9 species recorded today on MDI. However, there are only six species in common between historic and modern times. Procter identified four species that are no longer present on MDI: three of which are cuckoo-bumble bees, and the other is the Rusty-patched Bumble Bee (Table 2). Additionally, there are three species that we have documented today that were not collected by Procter: Brown-belted Bumble Bee, Common Eastern Bumble Bee, and Sanderson’s Bumble Bee (Table 2).

Threatened and endangered species were another category we wanted to explore the status of on MDI. There were two species recorded that are currently listed as either state or federally threatened or endangered. Historically, Procter collected specimens of a Maine endangered species known as the Edwards’ Hairstreak (Satyrium edwardsii). Today, this species is barely found at 3 sites throughout the entire state of Maine. Another species, the federally endangered Rusty-patched Bumble Bee (Bombus affinis), has experienced a similar fate as the Edwards’ Hairstreak. This species was collected by Procter in the early 1900’s, and was once widespread across most of the eastern United States (U.S. Fish & Wildlife Service 2021). The Rusty-patched Bumble Bee has experienced large-scale range reductions and can no longer be found in most of the northeastern US.

Conclusions and Next Steps

It is apparent that iNaturalist observers recorded dramatically fewer species than Procter, but much of this can be attributed to the difference in methods: Procter’s intensive and long-term specimen collection method vs. the casual and minimally invasive photo documentation of iNaturalist. Based on this analysis, we cannot conclude that a species found by Procter but not recorded in iNaturalist is absent or decreasing. We can, however, be confident in determining that species not found by Procter but documented in iNaturalist are present and increasing. It may be that closer examination of these species and the reasons for their range expansion might tell us something about the species we aren’t finding.While iNaturalist’s methods are much safer and less invasive, there are limitations as many insects can only be identified to species in the hand with equipment such as loupes, microscopes, etc. That said, we would not have the modern data set for comparison without community efforts by citizen scientists. Continued careful and extensive photographic evidence collected via iNaturalist can be subsidized with intensive, scientist-led bio-blitzes to get a better understanding of the insect populations of MDI.

The bumble bees are a great example of pollinators to look into due to many researchers and projects focused on this group. Of the four species that are no longer found on MDI, three are cuckoo-bumble bees, a group that invades other bumble bee colonies, kills the queen, and takes control of the workers. These species have been undergoing large-scale range reductions, and some of this can be attributed to their host species also decreasing (Colla et al. 2012). An example is the Ashton’s Cuckoo-Bumble Bee, and its host, the Rusty-patched Bumble Bee which is now federally endangered because of its population loss (more on this species below). There were also three species of bumble bee that have become present on MDI since Procter was surveying the area. These three now occur here for various reasons. The Brown-belted Bumble Bee has been linked to human-developed land, increasing as planted meadows, roadsides, and urbanization have become more common (Novotny et al. 2021). Somewhat similarly, the Common Eastern Bumble Bee has shown impressive range expansion due to human introduction and commercialization of bumble bees (Palmier & Sheffield 2019). This species is also thought to be replacing species that have decreased due to landscape and climate change, such as the Rusty-patched Bumble Bee, due to its highly generalized habitat use (Palmier & Sheffield 2019). The Rusty-patched Bumble Bee has experienced large-scale range reductions, once having been present on MDI, but now cannot be found in the state of Maine (U.S. Fish & Wildlife Service, 2021). This species requires grasslands and prairies, an ecosystem that has taken devastating losses due to degradation, fragmentation, and conversion to industrial agriculture or development (U.S. Fish & Wildlife Service, 2021).

According to the MDIFW Endangered Species Program (2003), the Edward’s Hairstreak has undergone a major range restriction and today has only been found at three sites in southwestern Maine. The extensive reduction in abundance of this species can largely be attributed to the loss of their native habitat, pitch pine-scrub oak barrens, which have been reduced to less than 50% of their historic range due to climate change and human development along the coast (MDIFW, 2003).

Future research could incorporate additional data sets, such as bio-blitzes that were conducted from the early 2000s to 2016. The addition of these data will provide us with a more complete snapshot of what species are currently present on the island, and how we can make management recommendations to help the native insects of our region.

Modern Species not Recorded by Procter

Table 1. This table shows the 88 species that the iNaturalist community identified over the past 10 years that were not recorded by Procter in the 1900s. Data collected on Mount Desert Island, Maine, USA, and provided by iNaturalist and the National Park Service.

Click to show table

Order	Super family	Family	Scientific name	Common name
Hymenoptera	Apoidea	Apidae	Bombus griseocollis	Brown-belted Bumble Bee
Hymenoptera	Apoidea	Apidae	Bombus impatiens	Common Eastern Bumble Bee
Hymenoptera	Apoidea	Apidae	Xylocopa virginica	Eastern Carpenter Bee
Lepidoptera	Bombycoidea	Saturniidae	Callosamia promethea	Promethea Silkmoth
Lepidoptera	Bombycoidea	Sphingidae	Hemaris aethra	Diervilla Clearwing
Lepidoptera	Bombycoidea	Sphingidae	Manduca sexta	Carolina Sphinx
Lepidoptera	Gelechioidea	Gelechiidae	Arogalea cristifasciella	White Stripe-backed Moth
Lepidoptera	Gelechioidea	Autostichidae	Gerdana caritella
Lepidoptera	Gelechioidea	Gelechiidae	Scrobipalpula manierreorum
Lepidoptera	Geometroidea	Geometridae	Idaea dimidiata	Single-dotted Wave
Lepidoptera	Geometroidea	Geometridae	Macaria aemulataria	Common Angle
Lepidoptera	Geometroidea	Geometridae	Macaria pustularia	Lesser Maple Spanworm Moth
Lepidoptera	Geometroidea	Geometridae	Nematocampa resistaria	Horned Spanworm Moth
Lepidoptera	Geometroidea	Geometridae	Rheumaptera prunivorata	Cherry Scallop Shell Moth
Lepidoptera	Geometroidea	Geometridae	Xanthotype	Crocus Geometer Moths
Lepidoptera	Hepialoidea	Hepialidae	Sthenopis pretiosus	Gold-spotted Ghost Moth
Lepidoptera	Noctuoidea	Noctuidae	Acronicta fallax	Green Marvel
Lepidoptera	Noctuoidea	Noctuidae	Acronicta funeralis	Funerary Dagger
Lepidoptera	Noctuoidea	Noctuidae	Acronicta insita	Large Gray Dagger
Lepidoptera	Noctuoidea	Noctuidae	Acronicta oblinita	Smeared Dagger
Lepidoptera	Noctuoidea	Erebidae	Apantesis figurata	Figured Tiger Moth
Lepidoptera	Noctuoidea	Erebidae	Apantesis virgo	Virgin Tiger Moth
Lepidoptera	Noctuoidea	Erebidae	Arctia parthenos	St. Lawrence Tiger Moth
Lepidoptera	Noctuoidea	Nolidae	Baileya doubledayi	Doubleday’s Baileya Moth
Lepidoptera	Noctuoidea	Noctuidae	Bellura obliqua	Cattail Borer Moth
Lepidoptera	Noctuoidea	Noctuidae	Calophasia lunula	Toadflax Brocade Moth
Lepidoptera	Noctuoidea	Erebidae	Chytolita morbidalis	Morbid Owlet
Lepidoptera	Noctuoidea	Erebidae	Cycnia tenera	Delicate Cycnia Moth
Lepidoptera	Noctuoidea	Notodontidae	Datana contracta	Contracted Datana Moth
Lepidoptera	Noctuoidea	Erebidae	Doryodes spadaria	Dull Doryodes Moth
Lepidoptera	Noctuoidea	Noctuidae	Elaphria alapallida	Pale-winged Midget
Lepidoptera	Noctuoidea	Erebidae	Euchaetes egle	Milkweed Tussock Moth
Lepidoptera	Noctuoidea	Noctuidae	Eudryas grata	Beautiful Wood-nymph
Lepidoptera	Noctuoidea	Noctuidae	Eupsilia vinulenta	Straight-toothed Sallow
Lepidoptera	Noctuoidea	Noctuidae	Feltia herilis	Master’s Dart
Lepidoptera	Noctuoidea	Erebidae	Haploa clymene	Clymene Moth
Lepidoptera	Noctuoidea	Erebidae	Hypena manalis	Flowing-line Snout
Lepidoptera	Noctuoidea	Noctuidae	Lithophane baileyi	Bailey’s Pinion Moth
Lepidoptera	Noctuoidea	Erebidae	Lophocampa caryae	Hickory Tussock Moth
Lepidoptera	Noctuoidea	Noctuidae	Maliattha synochitis	Black-dotted Glyph
Lepidoptera	Noctuoidea	Erebidae	Mycterophora inexplicata	Pale-edged Snout Moth
Lepidoptera	Noctuoidea	Noctuidae	Neoligia exhausta	Exhausted Brocade
Lepidoptera	Noctuoidea	Noctuidae	Noctua pronuba	Large Yellow Underwing
Lepidoptera	Noctuoidea	Noctuidae	Oligia strigilis	Marbled Minor
Lepidoptera	Noctuoidea	Erebidae	Panopoda rufimargo	Red-lined Panopoda Moth
Lepidoptera	Noctuoidea	Noctuidae	Psectraglaea carnosa	Pink Sallow
Lepidoptera	Noctuoidea	Erebidae	Zanclognatha laevigata	Variable Fan-foot
Lepidoptera	Papilionoidea	Hesperiidae	Anatrytone logan	Delaware Skipper
Lepidoptera	Papilionoidea	Hesperiidae	Carterocephalus mandan	Arctic Skipper
Lepidoptera	Papilionoidea	Lycaenidae	Celastrina lucia	Northern Azure
Lepidoptera	Papilionoidea	Nymphalidae	Coenonympha california	Common Ringlet
Lepidoptera	Papilionoidea	Hesperiidae	Epargyreus clarus	Silver-spotted Skipper
Lepidoptera	Papilionoidea	Hesperiidae	Erynnis juvenalis	Juvenal’s Duskywing
Lepidoptera	Papilionoidea	Lycaenidae	Glaucopsyche lygdamus	Silvery Blue
Lepidoptera	Papilionoidea	Nymphalidae	Lethe anthedon	Northern Pearly-eye
Lepidoptera	Papilionoidea	Nymphalidae	Lethe appalachia	Appalachian Brown
Lepidoptera	Papilionoidea	Nymphalidae	Limenitis arthemis arthemis	American White Admiral
Lepidoptera	Papilionoidea	Hesperiidae	Lon hobomok	Hobomok Skipper
Lepidoptera	Papilionoidea	Lycaenidae	Lycaena phlaeas hypophlaeas	Eastern American Copper
Lepidoptera	Papilionoidea	Nymphalidae	Megisto cymela	Little Wood Satyr
Lepidoptera	Papilionoidea	Nymphalidae	Nymphalis l-album	Compton Tortoiseshell
Lepidoptera	Papilionoidea	Papilionidae	Papilio canadensis	Canadian Tiger Swallowtail
Lepidoptera	Papilionoidea	Papilionidae	Papilio polyxenes	Black Swallowtail
Lepidoptera	Papilionoidea	Nymphalidae	Phyciodes cocyta	Northern Crescent
Lepidoptera	Papilionoidea	Lycaenidae	Satyrium liparops	Striped Hairstreak
Lepidoptera	Papilionoidea	Nymphalidae	Speyeria cybele	Great Spangled Fritillary
Lepidoptera	Papilionoidea	Hesperiidae	Thymelicus lineola	Essex Skipper
Lepidoptera	Pterophoroidea	Pterophoridae	Geina buscki	Buck’s Plume Moth
Lepidoptera	Pyraloidea	Crambidae	Anania hortulata	Small Magpie
Lepidoptera	Pyraloidea	Crambidae	Donacaula longirostrallus	Long-beaked Donacaula Moth
Lepidoptera	Pyraloidea	Crambidae	Eoparargyractis plevie
Lepidoptera	Pyraloidea	Pyralidae	Hypsopygia olinalis	Yellow-fringed Dolichomia Moth
Lepidoptera	Pyraloidea	Crambidae	Microcrambus biguttellus	Gold-striped Grass-veneer
Lepidoptera	Pyraloidea	Pyralidae	Pococera expandens	Striped Oak Webworm Moth
Lepidoptera	Pyraloidea	Crambidae	Scoparia biplagialis	Double-striped Scoparia Moth
Lepidoptera	Pyraloidea	Crambidae	Sitochroa palealis	Carrot Seed Moth
Lepidoptera	Sphingoidea	Sphingidae	Sphinx poecila	Northern Apple Sphinx
Lepidoptera	Tortricoidea	Tortricidae	Acleris forsskaleana	Maple Leaftier Moth
Lepidoptera	Tortricoidea	Tortricidae	Archips dissitana	Boldly-marked Archips Moth
Lepidoptera	Tortricoidea	Tortricidae	Cenopis reticulatana	Reticulated Fruitworm Moth
Lepidoptera	Tortricoidea	Tortricidae	Eucosma ochroterminana	Buff-tipped Eucosma Moth
Lepidoptera	Tortricoidea	Tortricidae	Eucosma parmatana	Aster Eucosma Moth
Lepidoptera	Tortricoidea	Tortricidae	Gymnandrosoma punctidiscanum	Dotted Gymnandrosoma Moth
Lepidoptera	Tortricoidea	Tortricidae	Pelochrista derelicta	Derelict Pelochrista Moth
Lepidoptera	Tortricoidea	Tortricidae	Platynota exasperatana	Exasperating Platynota Moth
Lepidoptera	Tortricoidea	Tortricidae	Sparganothis tristriata	Three-streaked Sparganothis Moth
Lepidoptera	Zygaenoidea	Limacodidae	Apoda biguttata	Shagreened Slug Moth
Lepidoptera	Zygaenoidea	Limacodidae	Euclea delphinii	Spiny Oak-slug Moth

Comparisons by Insect Families

Figure 1. Comparison of the number of species by family from modern iNaturalist data and historical data collected by Procter in the 1900’s. Data collected on Mount Desert Island, Maine, USA, and provided by iNaturalist and the National Park Service.

Pollinators

Table 2. This table shows just the bumble bee species that modern day sources (iNaturalist, Acadia National Park BioBlitz, and Maine Bumble Bee Atlas) and Procter identified, and when they were present on MDI. Data collected on Mount Desert Island, Maine, USA, and provided by iNaturalist and the National Park Service.

Click to show table

Common name	Scientific name	Present 1900	Present modern
Ashton’s cuckoo bumble bee	Bombus ashtoni	yes	no
Brown-belted bumble bee	Bombus griseocollis	no	yes
Common eastern bumble bee	Bombus impatiens	no	yes
Confusing bumble bee	Bombus perplexus	yes	yes
Half-black bumble bee	Bombus vagans	yes	yes
Lemon cuckoo-bumble bee	Bombus citrinus	yes	no
Northern amber bumble bee	Bombus borealis	yes	yes
Rusty-patched bumble bee	Bombus affinis	yes	no
Sanderson’s bumble bee	Bombus sandersoni	no	yes
Tri-colored bumble bee	Bombus ternarius	yes	yes
Two-spotted bumble bee	Bombus bimaculatus	yes	yes
Yellow-banded bumble bee	Bombus terricola	yes	yes
Yellowish cuckoo-bumble bee	Bombus fervidus	yes	no

References

Colla, S.R., Gadallah, F., Richardson, L. et al. (2012). Assessing declines of North American bumble bees (Bombus spp.) using museum specimens. Biodivers Conserv 21, 3585–3595. https://doi.org/10.1007/s10531-012-0383-2

Maine Department of Inland Fisheries & Wildlife (MDIFW) (2003). State endangered: Edward’s Hairstreak (Satyrium edwardsii). https://www.maine.gov/ifw/docs/endangered/edwardshairstreak_106_107.pdf

National Research Council (2007). Status of pollinators in North America. The National Academies Press.

Novotny, J.L., Reeher, P., Varvaro, M. et al. (2021). Bumble bee species distributions and habitat associations in the Midwestern USA, a region of declining diversity. Biodivers Conserv 30, 865–887. https://doi.org/10.1007/s10531-021-02121-x

Palmier, K. M., & Sheffield, C. S. (2019). First records of the Common Eastern Bumble Bee, Bombus impatiens Cresson (Hymenoptera: Apidae, Apinae, Bombini) from the Prairies Ecozone in Canada. Biodiversity data journal, (7), e30953. https://doi.org/10.3897/BDJ.7.e30953

Procter, W. (1946). Biological survey of the Mount Desert Island region. Volume 7. The Wistar Institute of Anatomy and Biology, Philadelphia, US.

USDA (2021). 2021 USDA annual strategic pollinator priorities and goals report.

U.S. Fish & Wildlife Service (2021). Rusty patched bumble bee (Bombus affinis). Environmental Conservation Online System. https://ecos.fws.gov/ecp/species/9383