THE Cape Sable Seaside Sparrow, Ammospiza mirabilis (Howell),
was first discovered on the Cape Sable salt prairie by Arthur H. Howell
on February 18, 1918. Howell (1919) gave a complete description
of the bird and stated his reasons for believing that it should be given
specific rank. He later (1932) gave the history of the bird as known
up to that time. Although giving the range as, "an area about six
miles in length and not more than half a mile in breadth" on the coastal
prairie near Cape Sable, Howell mentioned Nicholson's (1928) finding
of a singing male about six miles northwest of Pinecrest and stated that
"further search in this region may show that the species has a wider
range than our present knowledge indicates." At the same time he
stated that "there is no country suitable for seaside sparrows on either
coast for a long distance northward." This last statement was born
of ignorance of the real conditions along the southwest coast of Florida,
perhaps excusable at the time. The two statements are entirely
contradictory, but in the light of present knowledge, the former was a
true prediction. Later investigations on the Cape showed that the
sparrows there ranged from Flamingo to behind Northwest Cape,
Semple (1936) and Samuel A. Grimes (oral). See map.
Sutton (in Holt and Sutton, 1926) described the labor involved in
finding this species and published an excellent colored plate of the
bird. However, observations in the field with 7 X binoculars at a later
measured distance of 36 feet did not disclose the amount of black in the
sub-orbital region displayed on the plate but did show the area as
described by Howell (1919). Any ornithologist, or bird watcher,
who must now rely on sight could do no better than to study both
Howell's 1919 description and Sutton's plate before attempting to
make a field identification.
Nicholson (1928) recorded finding a singing male of this species in
an open grassy savannah about six miles northwest of Pinecrest. Al-
though not doubting Nieholson's seeing of the bird at some point,
the location as given was so fantastic as a habitat for a Seaside Sparrow
that no one actually familiar with the Pinecrest area could give the
location much credence. Pinecrest, in 1928, was a small village
located on the southernmost segment of the Loop Road (originally
surveyed to be the Tamiami Trail). The location is 20, or more,
miles from the nearest point on the Gulf of Mexico. Any point north-
west of Pinecrest would be, moreover, in the very heart of the cypress
(Taxodium distichum) swamps covering the area. Nicholson (1938)
again mentioned this place, writing that in 1932, with Joseph C.
Howell, Jr., the sparrows had again been found there; but that in
1937, with Arthur H. Howell, John B. Semple, and others, no sparrows
could be found,--"in the savannah 7 miles north" (sic) "of Pinecrest."
Correspondence between the author and Nicholson and J. C. Howell,
Jr., in 1952 established the fact that the actual location was on a
savannah extending out towards the coast from the Lostmans Pine
Islands area southwest of Pinecrest, the confusion apparently having
been due to the windings of the Loop Road and failure to study a
map of the area. In Sprunt (1954) this location was more correctly
given by the author but lack of space prevented any explanation of
the change from Howell (1932).
During the years from 1918 to 1935 many specimens of this bird
were taken on Cape Sable for various museum and private collections.
Nests, eggs, and young were found; and some determinations of the
food habits were made from stomach analysis, see Howell (1932) or
Sprunt (1954). It would be interesting to know how many people
actually saw the live bird during that period.
On September 2, 1935, the most violent storm on record in the west-
ern hemisphere struck the Keys and the Cape Sable area (Tannehill,
1945, and the United States Weather Bureau, 1935). The center of
the storm passed over Long Key at 9:20 P.a., and traveling at ten
miles per hour, it must have reached the vicinity of Cape Sable about
midnight. The center of the storm passed Cape Sable at an unde-
termined distance at sea, but supposedly within a few miles. At
Long Key the center was preceded by a hurricane wave of 15 to 20
feet and accompanied by winds of 150 to 200 miles per hour with
gusts exceeding 200 m.p.h. "Reports agreed in the description of
the great rapidity with which the rise of the sea came in from the
southern side of the Keys as a 'wave of water' or a 'high wall'."
Cape Sable was buried under a wave of eight feet or more. Members
of the Roberts family then living at Flamingo had received radio
warning and started to walk out just prior to the arrival of the hurri-
cane wave. On December 6, 1935, the elder Mrs. Roberts told me
that when they reached the road along the bank of the Flamingo
canal the water in the canal was very low, but within a few minutes
the water was up to their armpits; and the only thing which saved
their lives was the recent elevation, of about two feet, of the road
along the canal bank. Going westward from Flamingo that same
day I found a line of bleached seaweed festooned for long distances in
the trees about eight feet or more above the normal high water mark.
GULF
OF
MEXIGO
LE6END
,- SALT PRAIRIE
-SALT MARSH
'/- WET PRAIRIE
,x%%-MARSH PRAIRIE SAW
GRASS, TREE HAMMOCKS i
_-PINE
Illill-CYPRESS
.-',-EDGE OF MANGROVES
/'-ROUTE TRAILS
-CAPE SABLE SEASIDE
SPARROW OBSERVATIONS
i-HOWELL, ET AL.,1918-1935;
2-5- NICHOLSON 1928.
4-ANOERSON 19,2 52HARDY
ALL OTHERS-' STIM'SON, ET AL.
o 5
SCALE - MILES
SHARK
RIVER
FLORIDA OBA"Y
FmxJR 1. Map of the southwestern tip of '1orida, showing the range of the
Cape Sable Seaside Sparrow.
It seems incredible that any small sparrow could have escaped alive.
If any sparrow did manage to get into the air when that eight foot
wave struck, it would have been blown to sea towards the center of
the storm and would have dropped from exhaustion into the waters
of the Gulf long before the storm again crossed land in the vicinity
of Cedar Keys, far up the west coast of Florida. To my knowledge
no reports have ever come from that part of the coast of the presence
of this species since the storm. Semple (1936) does state that the
bird was in its usual haunts on Cape Sable in April, 1936. That he
must have been mistaken in his identification seems apparent from
later information. Nicholson (1938) states that Mr. Semple was
with a party consisting of Arthur H. Howell, Thomas D. Burleigh,
and others on May 19, 1937, at Cape Sable, and though they all
searched areas where they had formerly found the bird, none could
be found. Burleigh (1939) states that he and Mr. Semple searched
the area on December 8, 1938, but no sign of any sparrow was found.
During the winters from 1946 to 1950 many reports came from the
area of the presence of the Cape Sable Seaside Sparrow. In most
cases the bird seen was simply the common-in-winter Savannah
Sparrow (Passerculus sandwichensis). In other cases, Sharp-tailed
Sparrows (Ammospiza caudacuta) having a similar flight pattern may
have been mistaken for Cape Sable Seaside Sparrows. In fact
scratch feed was put out near the fishing camp and boat livery on
the canal near Flamingo which attracted the Savannah Sparrows.
Many people were told, or believed, that they were Cape Sable Seaside
Sparrows. On May 14 and 29, 1949, Robert Woodmansee and I
combed the entire prairie from Flamingo to a point about 1 iX miles
to the west where the Homestead Canal enters Lake Ingraham and
could find no trace of any sparrow. Both were familiar with .4. mira-
bills and its song in its Collier County breeding area. If present in
winter, this bird would be present in summer. The irrefutable fact
remains that since the 1935 storm no Cape Sable Seaside Sparrow
has been observed or reported from Cape Sable during the period
from May 15 to August 1; during which period no other species of
sparrow would be present, and the Cape Sable Seaside Sparrow would
be in song and easily found. It seems obvious that all sparrows of
this species then present on the Cape were destroyed by the 1935
storm.
Many began to feel that the species had followed the Great Auk
into oblivion. However, such was not the case. Nicholsoh's find
in 1928, and 1932, preceded the 1935 storm. The error in location
as published was unfortunate. However, we now know that the
sparrows were in the presently known range long before the hurricane.
They were not blown up there by the storm. It is my belief that they
have existed there since their evolution.
The new locations given later in this article were determined by
the view of a singing male during the breeding season, and two speci-
mens were taken near Ochopee and were sent to the National Museum
for the Fish and Wildlife Service collection, see Stimson (1953).
Anderson (1942) and Stimson (1944 and 1948) record a colony in
southern Collier County. The four men who knew of this location
felt that it should not be divulged exactly until a definite establish-
ment of more colonies had been made. It can now be told that the
spot was in the marsh close to the corner of the Tamiami Trail and the
road running north to La Belle from Everglades (city). In Sprunt
(1954) I listed two other locations in the neighborhood, together with
a location found in 1949 by Lamond Hardy southeast of Pinecrest.
The two specimens taken in 1952 were obtained at the location about
a mile east of the Anderson discovery point.
Nicholson has written me that in an old notebook for 1928, recently
found by his wife, he had recorded hearing several A. mirabills songs
on the north side of the Tamiami Trail about a mile west of the
Everglades crossroad. Both alone and in company with William G.
Atwater, I have searched at several points westward from the most
westerly known colony (about two miles west of that crossroad) as far
even as the small marsh near Shell Island south of Naples, but no more
colonies have been found in that direction. The search was confined
to the southerly side of the Tamiami Trail. West of the Everglades
crossroad there are several areas of salt and transition marsh on the
northerly side of the Trail, and further search may reveal the presence
of colonies there.
Soon after its publication, I secured a copy of Davis (1943). The
vegetation map accompanying this bulletin showed the presence of
salt marsh lying to the landward of the mangrove fringe all the way
from Shell Island, south of Naples, to the Shark River Basin. Having
known of the existence of the Cape Sable Seaside Sparrow in the acces-
sible marsh near Ochopee and Everglades, I felt that the species
probably existed in many suitable places all along that southwest coast,
and so stated in Stimson (1948). That supposition has now been
proved true.
On April 3, 1953, I found A. mirabills in the salt marsh amongst
an extensive growth of marshhay cordgrass (Spartina patens) about a
mile and a half southwest of Ochopee and since have shown the
species to many people at that point. On July 11, 1953, William G.
Atwater and I found the species in high Spartina grass west of, and
close to, the Turner River near the edge of the mangrove fringe. On
May 16, 1953, we walked the old oil well trail from the Loop Road
about half a mile west of Pinecrest, continuing southwest through the
cypress to one of the Lostmans Pine Islands group, but were turned
back by high water on the open prairie beyond and lack of time,
without finding any sparrows. On May 2, 1954, we attempted to
get to the salt marsh in the vicinity of the headwaters of the Chatham
River, starting from the curve on the Loop Road five miles south of
Monroe Station, but owing to high water and soft ground, we were
unable to get more than half way by noon and had to turn back.
On April 25, 1954, I was allowed by the Everglades National
Park authorities to accompany Rangers Erwin Winte and Fred
Devenport on a trip by caterpillar tractor swamp-buggy to a water
gauge just inside the park boundary about four and a half miles west
of the Monroe-Dade County Line. From the saw grass (Mariscus)
some two miles or more north of the water gauge a sparrow was
flushed, which, as it flew away with the sun on its back, showed the
characteristic greenish cast of A. mirabills. At the water gauge we
heard the song of A. mirabills two or three times in the distance,
but were too busy extricating the bogged-down machine to go and
check the birds. This point is about four miles from the spot where
Hardy found the birds in 1949, and amazingly both were in fresh water
saw grass.
In years of normal rainfall this whole southwest coast marsh area
during April, May, and later is accessible only by air-boat, or perhaps
helicopter. Neither is hardly the type of conveyance from which to
seek a small bird. The first four and a half months of 1955 proved
to be the driest similar period since 1928, according to the Miami
Weather Bureau. Up to 5:00 P.a. on May 15, 1955, the rainfall for
the period had been only 3.99 inches, as compared to 4.05 inches
through May 15, 1928. Only a 0.15-inch fall of rain during the
evening of May 15 kept 1955 from breaking the all time record. The
whole region had practically dried up. It became possible to walk
anywhere northwest of the Shark River Basin out to the mangrove
fringe completely dry-shod. A swamp-buggy could go easily almost
anywhere. I attempted to take all possible advantage of this drought
condition.
On April 8, 1955, I walked from the Loop Road, five miles south
of Monroe Station, southwesterly to the mangrove fringe near the
headwaters of the Chatham River. The prairie at that point was
quite narrow, and there were only a few small patches of Spartina
grass. Being there from 11:00 2t.M. to 1:00 P.M. was not the best time
of day to find Seaside Sparrows in song. The day was bright and
hot, and if any sparrows had been present they undoubtedly would
have kept down out of sight. None were found. The area did not
look very favorable as a habitat for them.
On April 16, 1955, I found A. mirabilis in tall Spartina grass near
the southerly end of the Barnes Strand (cypress) about eight miles
west of Monroe Station and three and a half miles south of the
Tamiami Trail. The plan had been to walk completely around the
Barnes Strand, but the Spartina grass became very high and dense,
and extremely hard to force one's way through, so the plan was given
up. The back track via swamp-buggy trail held out far more induce-
ments. In all, one Cape Sable Seaside Sparrow was seen singing, several
more were heard singing near at hand, and several were heard close
by in the grass giving the "zup-zup" call note described in Sprunt
(1954). Several were flushed which showed the greenish cast on
the nape as they flew off away from the sun. Savannah, Sharp-
tailed, and Swamp Sparrows (Melospiza georgiana) were also seen.
On April 23, 1955, I walked from the old saw mill site, about six
miles west of Pinecrest on the Loop Road, down an old lumbering
road to Gum Slough, where only a cupful of water remained in a
wheel rut. From there a swamp-buggy trail was followed through
the Lostmans Pine Islands and extensive prairie to the edge of the
mangrove fringe. A. mirabilis were found both in the salt marsh and
back up in the prairie-bay between two of the pine islands where the
cover was saw grass and other grasses. This prairie-bay was probably
within a mile or so of the supposed location of the 1928 Nicholson find.
With side forages, the round trip for the day covered about 18 miles.
Three hunter's cabins were found in the pine islands, one about four
miles from the Loop Road. On May 12 and again on May 28 I
packed in food, water, and blanket roll for two nights of camping
on each trip at the cabin nearest the Loop Road. On May 13
a route was followed south from camp to the open marsh, thence
southeasterly to the Everglades National Park boundary about
a mile east of the mangrove fringe. The day was bright and hot.
A. mirabilis were found at three points early in the morning. At
7:45 A.M. a bird was seen at close view swinging and singing on top
of a tall spear of grass. At. 8:03 A.M., near the edge of a slough
carpeted with purslane (Sesuvium portulacastrum) and bordered by an
extensive growth of Spartina grass, three birds were seen perched
in the tops of the grass as they sang. At 9:20 A.M. one Cape Sable
Seaside Sparrow was heard singing in the Spartina grass to the south.
Thereafter no more Seaside Sparrows were seen during the day, and
no other species of sparrows were seen that day. The mangroves
extended up into the marsh, or prairie, along the sloughs (apparently
the headwater creeks of the Lostmans River) leaving large prairie-
bays deep down towards the coast. I walked on a line to miss the
points of the mangrove extensions and may have missed many good
habitat locations of the sparrows. Lunch was eaten at the Park
boundary. Returning in the heat of the early afternoon, a direct
line was taken to the nearest point of pines about three miles away,
thence through the pines and intervening open prairie-bays back to
camp for a day's trip of about 17 miles. On May 29 a route was
taken westward from camp through the pine island to the open prairie-
bay bordered on the west by a cypress strand, apparently the spot
where Nicholson found the bird in 1928 and described to me in
a letter from Mr. J. C. Howell, Jr. No sparrows were found in
this prairie-bay (grassy savannah), but about two miles nearer the
mangrove fringe and within a half mile of the first sight of purslane,
A. mirabills were heard singing in an area of Spartina grass, one being
approached to within a later measured (paced) distance of less than
36 feet. Viewed through 7 X binoculars the bird might as well have
been in the hand. Altogether 12 Cape Sable Seaside Sparrows were
seen and heard singing along the transition marsh, containing in
places some saw grass, as far northwest as the wide slough (then dry
but apparently a small lake in wet weather) into which Gum Slough
empties. More about this spot later. The round trip distance for
the day from 6:30 A.t. to 2:30 v.t. was about 15 miles.
On May 7, 1955, Charles M. Brookfield, his brother Richard, Wil-
liam G. Atwater and I engaged Don Poppenhager to take us by
swamp-buggy, with permit from the Everglades National Park
authorities, down to the headwater creek of the Broad River on the
edge of the Shark River Basin. Starting at Pinecrest our course
took us within about three-eighths of a mile from the water gauge
visited in 1954. At a point about two miles north of the park bound-
ary we flushed a light-colored sparrow. The buggy was stopped and
I went on foot to check the bird. It had flown to a perch on a spear
of saw grass in plain view, and all heard the song of the Cape Sable
Seaside Sparrow. Again at a point about half a mile from the last
mangrove clump at the head of Broad River, I checked a bird on foot,
and another bird close by sang the A. mirabilis song. Having care-
fully checked their presence in the area, we counted during the day
from the buggy 56 light colored sparrows which, as they flew away from
the sun, showed the typical greenish nape of the Cape Sable Seaside
Sparrow. Many others flying into the sun were not counted. Also dur-
ing the day about 20 Swamp Sparrows and 50 Grasshopper Sparrows
(Ammodramus savannarum) were observed. Atwater and I walked
over to the last mangrove clump at Broad River and found water
which was entirely sweet to the taste. Atwater was surprised to
find pond apple (Annona glabra), wax myrtle (Myrica cerifera), and
cattails (Typha latifolia) in association with red mangrove (Rhizo-
phora mangle). Along the slough Sesuvium was found, indicating the
presence of salt underneath, even though the surface water was fresh.
From Broad River the swamp-buggy went northwestward across
the head of Rodgers River, crossing in water. Far back inland Don
had driven the buggy up to the edge of an alligator hole, perhaps 30
feet in diameter, still having water. There were only three places
at which water was found during the entire day. However, ap-
proaching Broad River the surface was damp and the buggy was
inclined to bog down. When it did so we all got off and walked it
up out of the hole, Don having left it in low gear. (It was the same
swamp-buggy portrayed in the National Geographic Magazine a few
years ago in connection with an article describing a trip from Lake
Okeechobee across the everglades to the southwest coast. The
buggy has two rear axles, each with two large wheels on each side,
the tires on the leading axle being equipped with tire chains. The
two axles are hooked up in a tandem drive with two transmission
boxes of three gears each.) Some distance further up the coast,
probably within two miles of the point where I lunched on May 13,
we were buzzed by an airplane. A note was dropped requesting that
Don go to a point about a mile south of "ten-mile corner" where
smoke had been seen rising from two hammocks, check on the fire
and report to Ranger Winte on our return. Waving the requested
signal of "something white" we spent the rest of the afternoon on
that endeavor, noting A. mirabills at three points, two of them again
north of the park boundary. See map.
Dr. Sloight, of the Department of Geology at the University of
Miami, stated in a public lecture at a meeting of the Tropical Audu-
bon Society that in the last sixty years there has been a five-inch
rise in sea level along the southwest coast of Florida. Davis (1943)
states that the red mangrove will live in fresh water. Indications
point to the fact that red mangrove seedlings float up on the fresh
water marshes, take root and grow slowly until the rising salt water
reaches them, after which they make more extensive growth and
increase in numbers. Nicholson (1950) comments on the disappear-
ance of the Smyrna Seaside Sparrow (A. m. pelonota) from a marsh
near New Smyrna owing to mangroves having taken over the entire
marsh. On July 11, 1952, Mr. R. J. Longstreet pointed out this spot
to me. Twelve years ago the marsh at the Anderson location was
free of mangroves, but while passing there on May 21, 1955, I noted
that much of the marsh, even up close to the Tamiami Trail, was
peppered with seedling red mangroves. In 1950 I noted a tidal
action in that marsh right up to the bank of the Trail; the marsh
being dry in the morning, and, without rain, being covered by an
inch of water in the afternoon. In 1955 a distinct tidal effect was
noted in the Tamiami Trail canal about nine miles easterly of the
Barron River canal. In rainy seasons the marshes at Ochopee (and
probably all along the southwest coast) are covered with fresh water
on the surface, but such dominant plants as Sesuvium portulacastrum,
Juncus roemerianus, and Spatrina patens indicate the presence of salt
underneath.
From where Gum Slough exits onto the prairie northwestward to
near the headwaters of the Chatham River, the red mangroves have
encroached in many places right up to the cypress strands, and most
of the existing prairie is broken up by scattered clumps of mangroves.
Apparently some cypress has been killed by the recent five-inch
rise in sea level, evidenced by the presence of dead trees standing
out on the prairie in front of the present strands. The effect of this
rise in sea-level seems to be shown very clearly at the mouth of Gum
Slough on the north side. The cypress strand comes down along Gum
Slough to a point on the edge of the prairie where it turns northwest-
ward. About 200 feet out in the prairie there stands a hardwood
hammock, containing also some cabbage palms (Sabal palmetto)
and some cypress. The whole hammock is surrounded by a fringe
of red mangroves. At the point itself there are red mangroves right
up against the cypress. The slough from the point outward is carpeted
with purslane. Starting at the point a wedge of tall Spartina grass
widens out towards the northwest. Immediately between the Spar-
tina grass and the cypress there is a wedge of tall saw grass which
also widens out towards the northwest. Towards the southwest the
mangrove clumps increase in numbers, size, and height towards the
coast. Water marks on the mangrove roots indicate that in years of
normal rainfall this part of the prairie would be almost a river, per-
haps fresh on the surface and salt underneath. It looks very much
as though a hiatus has built up, or is building up, separating the Sea-
side Sparrow colonies southeast of Gum Slough from the colonies
found in normal Spatrina habitat northwest to the Ochoe marshes.
The hiatus apparently extends from the Gum Slough entrance to
northwest of the headwaters of the Huston River. With the destruc-
tion of the salt marsh and the adjoining wet prairie, the dense strands
of cypress must have forced the Seaside Sparrows to have moved to
the colonies on either side or to have perished.
In the region between Broad River and Rodgers River, the man-
groves apparently have destroyed much of the original salt marsh,
and the Seaside Sparrows have adapted themselves to a life in the
adjoining area, designated by Davis (1943) as everglades marsh
prairie. The fact that the growth of saw grass is short and sparse
in this region may possibly indicate the encroachment of salt under-
neath the surface, but since the condition exists at least as far inland as
the Tamiami Trail it is probably the result of other factors. Griscom
(1944) states that no bird hugs salt water more closely than the Sea-
side Sparrow and, "In a whole century the individuals that have been
found 5 miles from salt water are few and far between and in most
cases casual waifs." Yet here in southern Florida we have Cape
Sable Seaside Sparrows living amongst saw grass and other fresh
water grasses. On that May 7, 1955, trip someone offered the wit-
ticism that had the bird been discovered in this area instead of on
Cape Sable it might have been named the Saw Grass Sparrow, rather
than the Cape Sable Seaside Sparrow. The 1954 and 1955 location
north of the water gauge is about 6/ miles from the mangrove fringe.
The Hardy location is at least 7 miles from the mangrove fringe. The
Cape Sable Seaside Sparrows last seen on May 7, 1955, were between
9 and 10 miles from the nearest point on the mangrove fringe. Besides
these definite points there have been unconfirmed reports of this
sparrow much further inland. In other words there is an area of at
least 70 square miles, with more available, where the Seaside Sparrow
apparently lives in a fresh water habitat. There appears to be a
greater concentration of Seaside Sparrows in this area than in the
normal $partina patens habitats further up the coast. The final
ecological relationships of this phenomenon will have to be worked
out by a botanist-ornithologist, and someone with more financial or
institutional backing than have been at my disposal.
Griscom (1944) states that A. nigrescens has two claims to specific
distinctness but that A. mirabills has no real claim to specific distinct-
ness and is probably only an extreme development of the light phase
of A. maritima. Griscom goes on to say that the pure white under-
parts of mirabilis actually deprive nigrescens of one of its absolute
characters. The A.O.U. Committee on Nomenclature and Classifica-
tion of North American Birds does not recognize this viewpoint, and
according to its chairman, Dr. Alexander Wetmore, has decided to
treat both as full species in the forthcoming new A.O.U. Check-list.
However, in the field I have been impressed by the great similarity
of action and song of these two so differently colored birds. Both
birds give two or more preliminary guttural clicks before the normal
song. These clicks can be heard only if one is within about fifty
feet of the singing bird. The songs seem to vary only in the more
buzzing quality and strength of nigrescens.
It is perhaps idle to theorize on the way in which this sparrow
reached Cape Sable. The following ideas are based in part on the
geological history of the Florida peninsula. Certainly there were no
sparrows anywhere in Florida during the first (Aftonian), or second
(Yarmouth) interglacial stages, when according to Cooke (1939)
the sea level stood at plus 270 feet and plus 215 feet, respectively.
It may have been possible for Seaside Sparrows, if any were then in
existence, to have gained a footing on Floridian shores during sub-
sequent glacial stages of the Pleistocene Epoch. Beether (1955)
states,--"The Cape Sable seaside sparrow may have been isolated
when the lower third of Florida was inundated by the post glacial
rise in sea level." According to Cooke (1939) this inundation oc-
curred during the post-Iowan interglacial stage of Wisconsin time.
Surely no sparrows could have existed in southern Florida during
that inundation when the Pamlico Sea stood at plus 25 feet. During
the last part of the Wisconsin glacial era when the sea level dropped
to minus 25 feet or more, it might have been possible (and probably
was) for the ancestral sparrow to populate the west shoreline of
Florida then lying several miles out in what is now the Gulf of Mexico.
Retreating before the inexorable rise of the sea during the melting
of the final glacier of late Wisconsin time, the sparrows caught in the
flooding of Tampa Bay, Charlotte Harbor, and estuary of the Caloosa-
hatchee were destroyed, leaving the sparrows north of Tampa Bay
to develop the characteristics of the Scott's Seaside Sparrow (A. m.
peninsulae), and the sparrows south of Naples to develop the charac-
teristics of the Cape Sable Seaside Sparrow (A. mirabills).
To the seaward of the inland bays along the southwest coast there
are many areas of salt marsh scattered through the mangrove swamp,
pond, and stream region. On July 25, 1952, with Joseph C. Moore,
William G. Atwater, and William B. Robertson, I investigated several
of these marshes along the Joe River and upper Shark River (Tarpon
Bay). Salt-killed saw grass was present in some, and dominant
black rush (Juncus roemerianus) in all, but no sparrows were found.
These marshes are undoubtedly remnants of a salt marsh that at
some past time extended all along this coast from near Naples to Cape
Sable. Only in recognizing the presence of such a continuous marsh
does it seem possible to explain the former presence of the Cape Sable
Seaside Sparrow on Cape Sable.
Davis (1943) states that the deep peat deposits along the southwest
coast of Florida in the region between Shark River and Barron River
are now interpreted as indicating a rise of sea level of 7 to 10 feet in
recent geological times. Mr. Robert Ginsburg, then with the Marine
Laboratory of the University of Miami, told me that in 1953 he took
a core of peat from 75 to 101 inches deep in Florida Bay near Big Crane
Key on which a Carbon 14 dating was made by the U.S. Geological
Survey showing an age of 3300, plus or minus 240, years. It is evi-
dent that the 7- to 10-foot rise in sea level mentioned by Davis (1943)
has occurred within the last 3000 to 3500 years. This rise of 7 feet
or more would have flooded the present Shark River Delta, Oyster
Bay, and Whitewater Bay region, where the present depth of water
except for actual stream beds is now 4 or 5 feet, as shown by the U.S.
Coast and Geodetic Survey map No. 598. The Cape Sable Seaside
Sparrow had apparently reached its present stage of development
prior to that flooding, or some 3000 years ago, since the specimens
taken near Ochopee in 1952 were identical with specimens taken
on Cape Sable in 1918 and following years. When that flooding
occurred the Sparrows on Cape Sable were separated from the spar-
rows to the northwestward of the Shark River Basin. The present
hiatus of water and mangrove swamp in the Shark River-Whitewater
Bay region has prevented the sparrows from again spreading back to
Cape Sable following the 1935 storm and will probably continue to
prevent their doing so as long as present ecological conditions exist.
The map herewith shows approximately all points of observation
of the Cape Sable Seaside Sparrow. At present the species ranges
in the salt marshes lying to landward of the mangrove fringe along
the southwest coast of Florida from northwest of Everglades (city)
to near the headwaters of the Huston River; and in salt marsh and
fresh water marsh prairie from the mouth of Gum Slough to the Shark
River Basin. The Ochopee marshes are now the most accessible
location for anyone wishing to see this interesting species.
I wish to acknowledge my indebtedness to Mr. Daniel B. Beard and
Mr. Joseph C. Moore, superintendent and biologist, respectively, of the
Everglades National Park, for their aid and cooperation in making
several trips within the park possible; to Mr. William G. Atwater
and Mr. Charles M. Brookfield for their aid and companionship on
several investigating trips; and to Mr. Donald J. Nicholson and Mr.
Joseph C. Howell, Jr. for cooperation in establishing the approximate
location of their 1928 and 1932 site.
LITJ,RATUR CITED
ADRSO, W. 1942. Rediscovery of the Cape Sable Seaside Sparrow in Collier
County. Fla. Nat., 16: 12.
BCHR, W.J. 1955. Late Pleistocene Isolation of Salt Marsh Sparrows. Ecol.,
36: 23-28.
Bummu, T.D. 1939. Notes on a Recent Trip to Southern Florida. Fla. Nat.,
12: 95-96.
CooK, C.W. 1939. Scenery of Florida. State of Fla. Geol. Bull. 17.
Dvm, J.H. 1943. The Natural Features of Southern Florida. State of Fla.
Geol. Bull. 25.
GrSCOM, L. 1944. A Second Revision of the Seaside Sparrows. Louisiana State
Univ. Occ. Pap. Mus. Zool., 19: 313-328.
HOLT, E.G., and G. M. SJTToN. 1926. Notes on Birds Observed in Southern
Florida. Annals Carnegie Mus., 16: 435-436, Plate 39.
HovLL, A. H. 1919. Description of a New Seaside Sparrow from Florida.
Auk, 36: 86-87.
HovLL, A.H. 1932. Florida Bird Life. Coward-McCann, Inc., New York.
NmuoLsoN, D.J. 1928. Nesting Habits of Seaside Sparrows in Florida. Wilson
Bull., 40: 234-237.
NmuoLsoN, D.J. 1938. An Historical Trip to Cape Sable. Fla. Nat., 11: 41-44.
NICUOLSON, D. J. 1950. Disappearance of Smyrna Seaside Sparrow from its
Former Haunts. Fla. Nat., 23: 104.
SrLr, J.B. 1936. The Cape Sable Sparrow and Hurticanes. Auk, 53: 341.
SrRuNT, A., JR. 1954. Florida Bird Life. Coward-McCann, Inc., New York.
STanDaRDiZeD PNT NMS. 1942. J. Horace McFarland Company, Harrisburg.
STsoN, L.A. 1944. Rediscovery of the Cape Sable Seaside Sparrow Confirmed.
Fla. Nat., 17: 31-32.
STsoN, L.A. 1948. Cape Sable Sparrow Still in Collier County. Fla. Nat., 21:
68-69.
Srso, L.A. 1953. Cape Sable Seaside Sparrow. Fla. Nat., 26: 57.
TNNHLL, I.R. 1945. Hurricanes. p. 84 & 214-215. Princeton Univ. Press.
UNITED STATS DPARTMINT OF COMMIRC, WJATHIR BUREAU. 1935. Monthly
Weather Rev., 63: 269-271, Plate 86.
P.O. Box 3303, Miami 21, Florida, July 15, 1955.