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Northeast Gulf Science Volume 2 Article 2 Number 1 Number 1

6-1978 Clapper Rail (Rallus longirostris) Studies in Alabama Dan C. Holliman Birmingham-Southern College

DOI: 10.18785/negs.0201.02 Follow this and additional works at: https://aquila.usm.edu/goms

Recommended Citation Holliman, D. C. 1978. Clapper Rail (Rallus longirostris) Studies in Alabama. Northeast Gulf Science 2 (1). Retrieved from https://aquila.usm.edu/goms/vol2/iss1/2

This Article is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf of Mexico Science by an authorized editor of The Aquila Digital Community. For more information, please contact [email protected]. Holliman: Clapper Rail (Rallus longirostris) Studies in Alabama

Northeast Gulf Science Vol. 2, No.1, p. 24-34 June 1978

CLAPPER RAIL (Rallus longirostris) STUDIES IN ALABAMAl

Dan C. Holliman Biology Department Birmingham-Southern College Birmingham, AL 35204

ABSTRACT: The habitat and distribution of the clapper rail Rallus longirostris saturatus in salt and brackish-mixed marshes of Alabama is described. A total of 4,490 hectares of habitat is mapped. Smaller units of vti'getation are characterized in selected study areas. A comparison of these plant communities and call, count data is shown for each locality. Concentrations of clapper rails generally occurrecj in those habitats with the higher percentage of Spartina alterniflora. A census techni­ que utilizing taped calls is described. Trapping procedures are given for drift fences and funnel traps. Life history data are presented including an early date of April 1 for first eggs in Alabama. Seven stomachs from summer birds yielded remains of Uca and unidentified seed material.- R. 1. satu1·atus was the only subspecies found during winter and summer surveys.

Clapper rails are permanent residents several remote off-shore islands and along the Alabama Gulf Coast. They are other less accessible coastal regions were found in sound and bay areas and along thought to afford an unknown potential coastal rivers and creeks where salt­ for rail habitat. Earlier field work also marshes and brackish-mixed vegetation suggested a need to determine pro­ persist. Little is known of the biology ductivity and to gather more concrete of clapper rails in this area. This popu­ life history data. lation has not been subjected to hunter Clapper rails have always been abun­ hmvest in Alabama (Mangold, 1977), dant in Alabama tidal marshes. In earlier where rail hunting IS practically years there were significant stretches of nonexistent. The lack of extensive marshland along the shores of Mississippi habitat and significant high tides that Sound, Mobile, Weeks, Bon Secour and would concentrate large numbers of birds Perdido Bays. Surveys begun by the in small areas probably accounts for the Coast and Geodetic Survey in 1856 lack of hunting pressures. Thick marsh mapped almost twice the area of tide­ vegetation and shallow water even at lands that are present today. Howell high tides discourage hunters from using (1928) reported the clapper rail plentiful boats and dogs. on Dauphin and Petit Bois Islands and It was thought that northern races in the Perdido Bay marshes. He also may winter along the Alabama coast. found it on Blakely Island in Mobile Field observations in the late 1960's River and in the marshes around Bayou suggested that concentrations of these la Batre. The coastal marshes of Alabama birds used certain areas for nesting, and began to decline noticeably by the early that the local population experienced an 1950's (personal observations). By the increase during the winter. Moreover, mid 1960's low areas along the Mississippi Sound and the bay areas of Baldwin 1 County were filled with dredge spoil, This research was funded by the Accelerated and much of the existing natural beaches Research Program for Migratory Shore and Up­ were replaced by seawalls (Traylor, land Game Birds, U. S. Fish and Wildlife Ser­ vice, Contract No. 14-16-000-8-703, July 1, 1971). In 1969 tropical storm Camille 1973 to August 31, 1976. virtually destroyed the exisiting marsh- 24

Published by The Aquila Digital Community, 1978 1 Gulf of Mexico Science, Vol. 2 [1978], No. 1, Art. 2

Clapper Rail in Alabama 25

land on the west end of Dauphin Island. from 5 to 15 ppt at least part ofthe year. Crance ( 19 71) recorded approximately This habitat type is characterized by S. 19,357 acres of emergent plants in alterniflora and giant cord grass, S. Mississippi Sound, Mobile Bay, Perdido cynosuroides. S. alterniflora may be Bay and Little Lagoon. Chermock greatly reduced and typically forms thin (1975) tabulated approximately 15,052 borders around brackish-marshes. S. acres of tidal marshland in these areas. cynosuroides is usually found at slightly However, he included 781 acres of higher elevations and is generally more fresh-mixed marsh. Vittor and Stout abundant than S. alterniflora. Other (1975) mapped nearly 16,000 acres of dominating plants in brackish-mixed salt marsh and brackish-mixed marsh in marshes include J. romerianus, Distichlis the Alabama coastal zone. Imhof (1976) spicata (salt grass), Borrichia frutescens described the clapper rail to be abundant (sea ox-eye), and Scirpus spp. (three but strictly confined to salt marshes. square). Sagittaria falcata (duck potato) Holliman (1977) reviewed the status of generally marks the transition zone be­ rail and gallinule habitat on a range wide tween brackish-mixed and fresh-mixed basis and projected a ten year manage­ marshes. ment plan for these wetland resources. Within both salt and brackish-mixed The purpose of this paper is to de­ marshes saltbush communities may be scribe the existing habitat and dis­ present in areas of raised elevations. tribution of Rallus longirostris, Boddoert Baccharis halimifolia (saltbush), and in Alabama, and include life history data Iva frutescens (marsh elder) characterize and field techniques. this plant association. Saltflat communities may interdigitate the inland border of both salt and MATERIALS AND METHODS brackish-mixed marshes. These exposed areas are inundated only by very high Description of habitat wind tides and excessive water run-off. In the northern Gulf Coast portion of High soil salt concentrations are present. their range clapper rails are found in both Typically the saltflats are barren with salt and brackish-mixed marshes. In terms the exception of scattered communities of vegetation patterns these habitats are of spp. (glasswort), not usually clearly defined but blend Salicornia Batis (saltwort), and inseparably one into the other. maritima D. spicata certain bluegreen algae and diatoms. "Pure" saltmarshes are subject to con­ stant tidal flooding and experience salinjties over 15 ppt at least part of the Selection of Study Areas year. This habitat type is characterized Small units of cover were selected so by smooth cord grass, Spartina alterni­ that detailed vegetative and population flora, which is most abundant where studies could be made. Likely-looking wave action is mitigated and accretion locations for study areas were examined occurs. Saltmarshes also contain in­ by air, then reached by truck or boat clusions of black needle-rush, ]uncus and subsequently explored on foot. Areas roemerianus, at slightly higher elevations. were closely examined where there were Brackish-mixed marshes, on the other abundant signs such as old nests, tracks, hand, are subject to fresh water, some or evidence of feeding. Numerous calls tidal flooding and experience salinities as well as flushed birds led to the final https://aquila.usm.edu/goms/vol2/iss1/2 2 DOI: 10.18785/negs.0201.02 Holliman: Clapper Rail (Rallus longirostris) Studies in Alabama

26 D. C. Holliman

selection of specific study areas. The Todd (1972). Counts were made in each boundaries of each location were esta­ study area during May, June and July of blished at the fartherest points that each year. The survey was conducted by clapper rail signs could be found in all playing the eastern clapper "Kek" and directions. These parameters were mea­ "Clatter" call at 50 meter intervals along sured on the ground and checked against the transect. The number of stops where topographical maps and aerial photo­ the tape was played varied according to graphs (See Fig. 1 ). A digital planimeter the length of the transect. Various hours was used to compute exact acreage for were tried to determine the most pro­ each tract. A transect was then plotted ductive periods of the day. Weather data as close to the longitudinal axis of each were collected and recorded. If readings area as possible. These transects necessar­ exceeded 2 (Beaufort scale) for either ily conformed to local topography and sky or wind the count was not made. ran the entire length of each study area. Taped calls were broadcast with a port­ They served as both call count routes and able Sony TC 900 tape recorder (use of transects for vegetative studies. V ege­ brand names does not imply endorsement tative data were gathered (m2) at 50 by the Federal Government). Both meter intervals along the transect. solicited and unsolicited calls were re­ corded only in one direction along the Census Technique transect to prevent counting the same A census technique was developed to birds twice. This technique of using locate concentrations of birds in the taped calls on a portable tape recorder study areas. The technique of using mag­ was also used to locate clapper rails in netically taped calls on a portable tape bay areas and along rivers. The boat was recorder was followed as described by stopped in likely areas where responses Varoujean (1972) and Tomlinson and could be elicited. This method proved

MOBILE BAY

30° BON SECOUR BAY MISSISSIPPI SOUND

GULF OF MEXICO ss• 88° 10'

Fig. 1. Clapper Rail habitat in Alabama: 1. Bayou laFourche, 2. Bull Bay Bayou, 3. East Marsh Is., Grand Bay, 4. Point aux Pins, 5. Little Bay and Litte River, 6. Isle aux Herbes, 7. Marsh Island, Portersville Bay, 8. Cat Island, 9. West Fowl River, 10. Heron Bay Bayou, 11. West end of Dauphin Is., 12.Little Dauphin Is., 13.Grave­ line Bay, 14. St. Andrews Bay, Little Point Clear, 15. Oyster Bay.

Published by The Aquila Digital Community, 1978 3 Gulf of Mexico Science, Vol. 2 [1978], No. 1, Art. 2 Clapper Rail in Alabama 27

highly effective in dense brackish-mixed Louisiana marshes, the rectangular box­ marshes that were otherwise inaccessible type trap with funnel entrances, as de­ except by boat. scribed by Bateman (1965) in a Louisiana A main objective of developing this study, was tried. It was thought that census technique was to locate concent­ this type would function more efficiently rations of clappers rather than to produce than a drop door trap since the ex­ an accurate index of the breeding pop­ tremely thick vegetation would hamper ulation. To achieve this objective and the mechanism of the moveable parts. stay within the time limitation, selected The Point aux Pins field station was areas were evaluated rather than attempt chosen as a trapping locality because of random sampling along the entire Ala­ its accessibility and relatively large num­ bama coast line. Because of inclement ber of birds as determined by the census weather on several occasions it was im­ technique. The basic differences in the possible to accomplish the same number study area at the Point aux Pins with of counts at each locality. Therefore the those studied by Bateman (1965) is a relative number of birds recorded at lack of significant high tides and a specific locations was not necessarily scarcity of extensive mud flats and indicative of the precise densities of the numerous interconnecting tidal "guts" clapper population there. or ditches of the former location. Two trap types were field tested Habitat Inventory during the study. A description of di­ A working copy of the vegetation maps mensions, construction and materials produced by Vittor and Stout (1975) follows. Both traps had two funnel en­ was traced on film and then checked by trances that were staggered so that a air flights and ground truth surveys to trapped bird would not pass out of the delineate clapper rail habitat. Small, trap once inside. One trap, a modified isolated areas less than 8 contiguous dove trap, was constructed of 2.5 x 3 .1 hectares or inclusions within larger em mesh weld wire with the funnels marshes that have been ecologically made of the same material. This trap disturbed were not plotted. Scattered was 86.4 em in length, 25.1 em in height pieces and small strips of marsh in bays and 45.7 em in width (Fig. 2). The and along rivers were also deleted. A other was constructed of 2.5 em mesh digital planimeter was used to compute heavy duty galvanized wire, 86.4 em in the area m the habitat inventory length, 30 em in height and 30 em in (Table 1). width. Funnels for this trap were con-

Trapping Table I. Salt marsh md br<~ckish m.tr:;h inventory (1976), of Alaham.t. Clapper rails have been trapped in LOCATION HECTARES J\lississippi line east to Grand Bay 626 other parts of their range by a variety Gr.tnd Bay including cast J.Ild west 1\brsh Islands 85 Point aux Pins, Sandy lhy and Little Rivt:r 243 of methods. Each method was deve­ Little River to Bayou La Batre 221 Cvden, north bank of West Fowl River and Grmd Point 471 loped to suit local field conditions. Be­ Heron Bay and ~Jon Louis 2,000 Isle aux Hcrbes (Coffee Island) 258 cause of the low water level even during Marsh Island, Portersville Bay 27 Cat Island 10 periods of high tide the use of air boats Cedar Point 30 Little Dauphin Island 196 with lights and nets at night was not Graveline Bay (Airport marsh) 135 West Dauphin Island 145 feasible. Because of the basic similarity St. Andrews Bay, Little Point Clear 28 Oyster Bay 15 --- of vegetation patterns of Alabama and TOTAL 4,490 hectares https://aquila.usm.edu/goms/vol2/iss1/2 4 DOI: 10.18785/negs.0201.02 Holliman: Clapper Rail (Rallus longirostris) Studies in Alabama

28 D. c. Holliman

structed of 1 em hardware cloth with the inner wires shredded in long strips to form a one way passage. The entrance for each funnel varied from 10 to 30 em wide and extended not more than 25.4 em into the trap. The innermost opening of the funnels was less than 2.5 em and in most cases the protruding wires from each side of the funnel almost touched. Both types of traps were pro­ vided with weld wire bottoms to prevent predators from killing trapped birds. Hinged doors, 35 x 30 em, were placed in the center top of each trap for the re­ moval of birds. Each trap was assembled with 1 em hog rings. Drift fences made of 2.5 em mesh, 60 em high and 46 m long were set in areas of abundant rail signs. An attempt was made to traverse tidal guts, trails, feeding platforms and tidal ponds with these drift fences. The traps were selectively placed along the length of the drift fence Figure 2. Devices for trapping clapper raiis. in likely places; with one side of the trap flush against the drift fence. An apron and 0.6m of water; 3) usually covered 1.6 m long, constructed of the same by more than 0 .6m of water. size wire as the drift fence, was extended RESULTS from the "outside" corner of each trap. Some aprons were positioned at a 45° Clappers were prone to answer calls angle while others were formed into an throughout the study period (Table 2). arch curving back towards the drift Both the "Kek" and "Clatter" calls as fence. The purpose ofthese aprons was to described by Tomlinson and Todd (1972) redirect birds back into the drift fence in were effective in eliciting reponses. case the entrance was initially bypassed. These were the most common calls and Some drift fences were erected in a frequently two or more birds would go straight line; others were placed to con­ into a "widely spaced" chorus. The form to existing features such as ponds, "Agitated Kek" and "Kek-burr" were nutria and muskrat lodges, etc. Wooden heard but were not as numerous as the stakes 1 m long and 1.3 em square were "Kek" and "Clatter" calls. Another call used to support the drift fences and heard in this study was a "Purr" call aprons and to secure the traps. given by a trapped immature bird while The traps and drift fences were placed held in the hand. This call was very low in three different areas in the marsh: in volume and resembled the purr of a 1) well above the high tide line, usually kitten. Another immature bird contin­ covered with less than 0.3 m of water; uously emitted a series of the "Agitated 2) usually covered with between 0.3m 1Purr" alarm notes thus called two adult

Published by The Aquila Digital Community, 1978 5 Gulf of Mexico Science, Vol. 2 [1978], No. 1, Art. 2

Clapper Rail in Alabama 29

rails within 1 m of the trapping area at bird giving the call. the Point aux Pins. On July 9, 1975 Table 3 characterizes and compares four first year birds were heard giving each study locality. These comparisons the "Hoo" call as they fed with adults are based upon the estimated per cent of at the mouth of Magnolia River. This Spartina and rails per hectares. The esti­ low "Hoo" call appeared to keep the mate of rails per hectares was based upon family unit together in thick vegetation size of study area, and teh average rather than serving as an alarm call. number of birds either seen or heard in Early morning and late evening times each study area during the study period. yielded the most data, at which time The number of counts indicate the there was less human interference and total number of times each study area disturbance from other bird species, was censused. The number of birds re­ such as laughing gulls and terns. Wind presents the total number of birds velocity and cloud cover appeared counted during the three year study to be the most significant environmental period in each locality. factors. Some birds answered but did not Study Specimens approach; some would approach and not All specimens examined by the in­ answer; others would both approach and vestigator during this study were refer­ answer. An attempt was made to spend no able to: more than 60 minutes along the length of Rallus longirostris saturatus Ridgway the transect. Wind speed probably had the Rallus longirostris var. saturatus greatest effect on detecting solicited "Henshaw" Ridgway, Bull. Nuttall calls. Birds usually responded immed­ Orn. Club, 5, no. 3, July 1880, p. iately to the taped calls, and because of 140. (Louisiana = Rigolets, Lake their "scattered" nature, the chorus Borgne, LA) effect as described by Gill (1972) did Five color phase and various degrees of not have a significant effect in reducing intermediates between these phases were the number of birds heard. No attempt encountered as follows (modified after was made to determine the sex of the Oberholser, 1937):

Table 2. Description of calls given by R. l. saturatus along the Alabama Gulf Coast.

Name of Call Description

Kek Regular spaced Kek-Kek-Kek-Kek call. Agitated Kek Higher pitched and more insistent than regularly spaced Kek call. Usually trilling down the scale towards end of call. Clatter Coarse with considerable more volume than the Kek call. Ker-burr Resembles the Kek call. Te.rminal notes with a trilled "brr" sound. Usually heard after Kek and Clatter calls. Purr Low purred note usually difficult to hear unless close to the bird. Agitated Purr A louder Purr call with more insistence. Can be heard at a great­ er distance than simple Purr call. Hoo Extremely low in volume and usually heard within family groups while feeding or moving through thick vegetation. https://aquila.usm.edu/goms/vol2/iss1/2 6 DOI: 10.18785/negs.0201.02 Holliman: Clapper Rail (Rallus longirostris) Studies in Alabama

30 D. c. Holliman

1. Light gray phase: Feathers of dorsum of each sex was established for bill length and scapulars with medium light to and middle toe length. A division point grayish-brown centers. Border broad for bill length of 60 mm and a division and clear gray. point for middle toe length of 48 mm 2. Dark gray phase: Feathers of dorsum was established. Birds with measurements and scapulars much darker with dark below these points are usually females. brown to blackish centers. Border These measurements fall within the broad and clear gray to darker. range given by Oberholser (1937). In 3. Light brown phase: Feathers of dorsum adult birds usually the distinction was and scapulars centrally dark with ru­ easily made by following these division fescent brown cast. Border light points. The method of aging chicks was olive brown. followed as described by Adams and 4. Dark brown phase: Feathers of Quay (1958). dorsum and scapulars very dark brown average of ten females - Wing 135 mm or black. Border light olive brown. (130-154), Bill 57 mm (54-66), Toe 5. Gray-breasted phase: Feathers of dor­ 40 mm (39-48) sum and scapulars resemble dark brown average of ten males - Wing 160 mm phase. Jugulum and breast clear to (141-164), Bill 65 mm (53-68), rather dark gray, not cinnamon. Toe 49 mm (43-53) one chick, nine weeks old - Wing 45 Measurements mm, Bill38 mm, Toe 47 mm Following a method used by Bateman one chick, eight weeks old - Wing 30 (1965) a division point between the mean mm, Bill38 mm, Toe 28 mm

Table 3. Characterization and comparison of clapper rail study areas along the Alabama coast. Type of Size of study Number of Number of !uncus Other Spartina Rails/ Location marsh area (hectares) counts birds % %' % hectare Marsh Island Portersville Bay Insular 6.1 2 32 10 5 85 2.64 Heron Bay Bayou Fringing 10,1 4 90 35 65 2.22 Isle .aux Herbes Insular 12.1 2 49 3 2 95 2.02 East Marsh Island, Grand Bay Insular 3.2 3 17 15 5 80 1.72 Graveline Bay (Airport marsh) Fringing 10.9 12 224 35 5 60 1.70 Point aux Pins Fringing 8.1 13 159 15 10 75 1.51 Cat Island Insular 5.7 3 23 30 20 50 1.36 St. Andrews Bay, Little Point Clear Fringing 8.1 2 20 50 10 40 1.24 Little Bay and Little River Fringing 20.2 3 71 30 20 50 1.21 Bayou Ia Fourche Fringing 2.0 3 7 90 10 1.14 West Fowl River Fringing 12.1 10 124 60 40 1.01 Little Dauphin Is. Insular 8.1 5 37 70 5 25 .91 Bull Bay Bayou Fringing 2.0 3 5 85 15 .84 Oyster Bay Fringing 8.1 2 5 80 5 15 .32 West End of Dauphin Island Insular 11.3 8 10 2 95 3 .12 Fringing- marsh bordering shoreline or tidal pools and bayous inside peninsular or mainland Insular- marsh bordering shoreline or tidal pools and bayous inside island

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Clapper Rail In Alabama 31

one chick, seven weeks old - Wing 29.9 raccoon, Procyon lotor. Twenty-eight mm, Bill 20.1 mm, Toe 20.7 mm nests were found that had been destroyed one chick, seven weeks old -Wing 25.2 by raccoons. Storm tides accounted for mm, Bill 24.5 mm, Toe 21.2 mm the destruction of 10 nests and 14 others were destroyed by undetermined causes. Eggs Eggs were taken April 1 to July 2 2; Food Habits downy young were taken May 3 to Stomachs from seven summer speci­ August 30. Egg data are summarized in mens yielded remains of Uca and some Table 4. seed materials. On August 6, 1975 a Forty eggs measured by Bent (1926) single clapper rail was observed feeding averaged 42 by 29.3; the eggs showing on a small fish in a tidal pool on the west the four extremes measured 46 by 30, end of Dauphin Island. The identification 41.2 by 31.6, 39.5 by 28.5 and 40 of the fish was not made. by 28.4. Trapping Nests A prediction cannot be made as to Nests were typically located close to which trap design or trapping area is the secondary and tertiary tidal creeks in most productive for Alabama marshes. large open areas of S. alterniflora that Approximately equal numbers of birds grew to 0.6 m in height. The minimum were caught and/or seen in each location. distance between active nests was 10 Numerous birds escaped through funnel m. It was not uncommon to find in­ entrances as evidenced by droppings and active "nests of the year" within 10 em feathers in empty cages. In three in­ of productive nests. No nests were stances birds were observed escaping found in pure ]uncus stands or in areas after having been trapped. Trapping where there was a mixture of only began on July 17, 1974 at the Point aux Distichlis and Spartina. Pins marsh and was terminated August Nests were built of uniform pieces of 16, 1974. Three hundred and seventy Spartina stems interwoven among the trap-days produced 10 birds. In 1975 living stems of this same species, thus trapping was resumed on July 20 and forming a platform with a slight con­ terminated August 3. One hundred and cavity. They were placed 15-25 em forty-four trap-days produced 5 birds. above the floor of the marsh. This height Heavy rains generated by three tropical usually accommodated the normal high depressions seriously hampered field tides. Some nests were provided a canopy activities in 1975. No trapping was of living Spartina leaves. Usually there attempted in 1976. would be a "ramp" of Spartina stems leading into each. Dispersed in the DISCUSSION thatched floor of successful nests could usually be found fragments of egg shells. Generally, the study areas containing At least two of the nests located during the most Spartina habitat also had the this study were used as a feeding plat­ highest density of birds. This is parti­ form after the young had hatched. cularly true for certain off-shore islands Apparently the principal predator on and other relatively inaccessible areas on the clapper rail in the study areas is the the mainland. Coastal Alabama lacks https://aquila.usm.edu/goms/vol2/iss1/2 8 DOI: 10.18785/negs.0201.02 Holliman: Clapper Rail (Rallus longirostris) Studies in Alabama

32 D. C. Holliman

Table 4. Measurements from eggs of six nests from the Point aux Pins study area in 1974. CLUTCH WEIGHT LENGTH WIDTH SIZE (G) (MM) (MM) 7 av 18.3 (17 .4) av 42.3 (40.2) av 29.8(29.0) 19.1 43.1 30.3 7 av 17.7 (16.3) av 41.0 (39.8) av 28.8 (27 .4) 19.9 42.2 29.4 7 no weight taken av 41.5 (40 .0) av 2 8.8 (28.6) 43.4 29.1 7 av17.6(16.7) no measurements no measurements 18.3 taken taken 6 av 17.5 (16.8) av 40.7 (39.0) av 29.6 (29.1) 19.1 42.0 30.2 2 no weight taken av 41.7 (41.5) av 30.5 (30.8) 42.0 30.3

extensive, uninterrupted expanses of gold, 1977). The Yuma Clapper Rail Spartina marshes. The southern portion (Tomlinson and Todd, 1972) is the only of the Isle aux Herbes, or Coffee Island subspecies found in brackish and fresh has the largest Spartina meadow in the water along the Colorado River between state at more than 125 hectares. Smaller Arizona and California in cattail (Typha "pure" Spartina marshes such as those latifolia) and tule (Scirpus acutus) on Marsh Island and Cat Island in Por­ marshes. During this Alabama study tersville Bay and East Marsh Island in rails were located in fringing Spartina Grand Bay, support significant popu­ marshes along West Fowl, Deer and Dog lations of clapper rails for their size. Rivers. Their distribution became more Degradations of Spartina marshes by disjunct in those rivers where there human development and by tropical was a paucity of Spartina. For example, storms within the last 20 years have re­ in Fish River, rails were located one­ duced considerably the amount of half kilometer up river from its mouth. Spartina cover for both Little Dauphin Solicited calls were also recorded from a Island and the west end of Dauphin small fringing marsh at the mouth of Island. Where "pure" stands of Juncus Magnolia River at Weeks Bay. These two occur, such as at the Bayou laFourche, Spartina marshes were less than 2 hect­ Bull Bayou and Oyster Bay study sites, ares and were surrounded by fresh-mixed low populations of rails were found. vegetation. Likewise the up river distri­ Searches for birds by using the tape­ bution of clappers in Little, East Fowl call technique as described in this paper and Bon Secour Rivers was limited were made in all of the Alabama coastal to small strips of Spartina less than rivers and creeks. In other parts of their fifty meters long and ten meters wide. range R. l. saturatus is commonly found No birds were found in the Mobile delta at the mouths of coastal rivers and along or east of Oyster Bay along the intra­ bayous wherever cordgrass occurs (Man- coastal waterway or in Perdido Bay where

Published by The Aquila Digital Community, 1978 9 Gulf of Mexico Science, Vol. 2 [1978], No. 1, Art. 2

Clapper Rai I in Alabama 33

there are no Spartina marshes. The distri­ contributed flight time for low level bution of clapper rails may also be in­ aerial inspection and photography during fluenced by the occurrence of Uca. The 1974. The Alabama Department of northern extent of Uca's territory in Conservation and Natural Resources the Alabama coastal zone is unknown. also provided plans for the trap design Freshwater may limit its range as well as that was modified during this study. that of S. alterniflora and S. cyno­ Hq 187th TAC RECON GP Dannelly suroides. ANG photographed and produced serial Since Spartina marshes are so impor­ imagery of the Alabama coastal region tant as habitat for clapper rails it is and off-shore islands both in 1974 and suggested that rough estimates of pop­ 1975. Remotely sensed imagery and high ulation size could be determined from in­ altitude aerial photography were ob­ spection of aerial photographs taken tained from the EROS center in Sioux annually. Air flights and ground truth Falls, SD. NASA at Bay St. Louis, MS surveys can be made to check for in­ made available their planimeter. accuracies in defining floral signatures. It has been shown that the tape-call LITERATURE CITED technique can serve as "point" checks for concentrations in given areas during Adams, D. A. and T. L. Quay. 1958. the nesting season when the birds are Ecology of the clapper rail in south­ most vocal. This information, coupled eastern North Carolina. Jour. Wld. with nesting density data, could be used Manag. 22(2): to determine population sizes for specific American Ornithologists Union. 1957. habitat types and sizes. These figures Checklist of North American birds. could thus be extrapolated to arrive at a Fifth Ed., A.O.U., Baltimore. total population estimate for a given Bateman, H. A., Jr. 1965. Clapper rail time. (Rallus longirostris) studies on Grand Terre Island, Jefferson Parish, La. M.S. ACKNOWLEDGMENTS thesis, Louisiana State University. Bent, A. C. 1926. Life histories of North The investigator wishes to acknow­ American marsh birds. United States ledge the help of the personnel and use Nat. Mus. Bull. 135. 490 p. of the facilities of the Marine Environ­ Chermock, R. L. 1975. The environ­ mental Sciences Consortium, Dauphin ment of offshore and estuarine Ala­ Island, Alabama and the Point aux Pins bama. Geological Survey of Alabama, Field Station at Bayou la Batre, AL. Information Series 51. 135 p. Special thanks are extended to Dr. J. Crance, J. H. 1971. Descriptions of Ala­ P. Stout for her invaluable suggestions bama estuarine area - Cooperative Gulf and assistance in the botanical studies. of Mexico Estuarine Inventory. Ala. I want to thank G. Gaston, T. Henwood Mar. Res. Bull. 6:1-85. and L. Eldridge for their help in the Gill, R., Jr. 1972. South San Fran­ field. Special thanks are also given to L. cisco Bay Breeding Bird Survey, 19 71. Lutz for her professional attention in Wildlife Management Branch Admin­ drawing the map and other biological istrative Report No. 72-6. Avian illustrations. The Alabama Department Biology Laboratory, Calif. State Univ., of Conservation and Natural Resources San Jose. https://aquila.usm.edu/goms/vol2/iss1/2 10 DOI: 10.18785/negs.0201.02 Holliman: Clapper Rail (Rallus longirostris) Studies in Alabama

34 D. c. Holliman

Holliman, D. C., 1977. Rails and Galli­ the clapper rails (Rallus longirostris, nules. p. 44-121. In: G. C. Sanderson Boddaert). Proc. U. S. Nat. Mus. 84 (ed.). Management of Migratory Shore (3018) :313-354. and Upland Game Birds in North Tomlinson, R. E. and R. L. Todd. 1972. America. International Association of Distribution of two western clapper Fish and Wildlife Agencies, Wash­ rail races as determined by responses ington, D. C. to taped calls. Condor 75(2):177-183. Howell, A. H. 1928. Birds of Alabama. Traylor, C. T.1971. The effects of human (2nd Ed.). Dept. of Game and Fish of activity on the bird colonies of the Alabama. Montgomery. offshore islands of Alabama and Miss­ Imhof, T. A. 1976. Alabama Birds. issippi. M. S. thesis, The University (2nd Ed.). The University of Ala­ of Alabama. bama Press, University, AL Varoujean, D. H. 1972. A study of the Mangold, R. E. 1977. Rails and Galli­ California clapper rail in Elkhorn nules. p. 84-92. In: G. C. Sanderson Slough. California Dept. Fish and (ed.). Management of Migratory Shore Game (manuscript). and Upland Game Birds in North Vittor, B. A. and J.P. Stout. 1975. De­ America. Intenational Association of lineation of ecological critical areas Fish and Wildlife Agencies, Washing­ in the Alabama coastal zone, Dauphin ton, D. C. Island Sea Lab Special Report No. Oberholser, H. C. 1937. A revision of 75-002.

Published by The Aquila Digital Community, 1978 11