SUMMARY Mean clutch size in 236 sets of North American Brown Pelican eggs was 2.95 and did not vary geographically between North American populations. Shell weight varied from 8.05 g to 10.99 g along a geographic continuum. Shell thickness averaged 0.510 mm for Pelecanus occidentalis occidentalis, 0.554-0.557 mm for P. o. carolinensis, and 0.569-0.579 mm for P. o. californicus. The ranges of breeding dates for the more southern populations were wider than those of northern ones. Small numbers of eggs taken in Texas and Florida after 1949 were 20 per cent below normal weight; 1962 eggs from California were 26 per cent below normal; and three taken in Panama, 15 per cent below normal. Shell thickness had likewise decreased 15-27 per cent.

ItE Gulf Coast population of the Brown Pelican (Pelecanus occidentaiis) is now considered to be endangered by the AOU Committee on Conser- vation (1968). The circumstances surrounding its decline are not clear. Murphy (1936:102, 808-822) suggested that some breeding populations of Brown Pelicans "normally" fluctuate in response to fluctuating food supplies in relation to such factors as Humboldt Current changes, as well as other factors. Conney (1967), Kupfer (1967), Peakall (1967), Risebrough et al. (1968), and Wurster (19'69') have explained some potential physiological effects of chlorinated-hydrocarbon and related environmental pollutants on mammalian and avian reproduction, which might apply, as well. This paper presents. information, obtained from major oological collections in North America, regarding some egg and reproductive parameters of the Brown Pelican. Ratcliffe (1967) and Hickey and Anderson (1968) have utilized oological sources to document changes in shell thickness and shell weight among seven species of birds. These changes. were related to (1) the widespread introduction of persisting chlorinated hydrocarbons into the environment and (2) reproductive failures associated with shell-breakage and loss. The lack of field data regarding certain breeding and egg characteristics from prior to and possibly during the decline of the Brown Pelican necessi- tated our attempt to glean whatever information possible from museum and private-egg collections. An understanding of the present situation, in addition, requires an evaluation of the geographical and temporal variations in the characters of interest. METItODS Measurements.--Eggs were weighed to the nearest 0.01 gram (g) on a torsion balance. Improper cleaning undoubtedly influences shell-weight and possibly also shell-thickness measurements. We used four criteria to determine if eggs had been properly blown: (1) a tendency to settle to one side when rolled on a smooth surface, (2) loose contents, (3) roughness on the interior of the shell, and (4) visual examination. In the course of measuring over 34,000 eggs of 25 species, we found about 200-300 broken or cracked eggs and a larger number with large holes. These lent themselves to close examination, and all proved to be satisfactorily cleaned. Eggs with holes larger than 7 mm were either not measured, or their weights were corrected to those with a 3-mm hole. This was ac- complished by taking a small piece of shell, weighing it, and visually "filling" the hole. Egg lengths and breadths were measured to the nearest 0.01 centimeter with a standard, precision vernier caliper. Egg shapes were determined by comparison with the shapes 14 Anderson and Hickey BROWN PELICAN EGG AND BREEDING DATA 15 TABLE 1 CLUTCH SIZES AND INCUBATION STAGES OF EGgS TAKEN BY OOLOGISTS PaIoa TO 1943 Est. Stage Incubation Sample Mean 95% of Incubation Rating Size Clutch Size C.L. First egg-3 days 1 72 2.94 0.32 4-12 days 2 137 2.93 0.31 13-21 days 3 27 3.07 0.50 22-30 days 4 0 -- -- All combined -- 236 2.95 0.27 This stage represents a period of approximately 9 days. described by Palmer (1962:13) and Preston (1968). Shell thickness was measured to the nearest 0.01 mm with a specially adapted micrometer, the procedure being described by Hickey and Anderson (1968). Thickness included shell and associated membranes at the girth of each egg. In]ormation ]rom Data Slips.--Data slips, giving species, date of collection, stage of incubation, location, collector, and other pertinent information accompanied each set of eggs we measured. Due to the inadequacy of incubation terminology and the inability to identify incubation stage accurately (Storer, 1930), mean dates of set-collection (corrected on the basis of reported incubation to give date of clutch completion) can only provide an estimate of breeding phenology. The dates together for an area really only represent a mean over the years, but do suggest general trends and provide an index to length and variability of breeding season from region to region. We felt that oologists' estimates of incubation could, at best, only be categorized to the nearest one- fourth of the period from first egg to the end of incubation. The incubation period of the Brown Pelican is not precisely known (Palmer, 1962:277). We have used Mason's (1945) estimate of about 30 days for our calculations here and have estimated the mean number of days that our samples were incubated on the basis of our four incubation categories (Table 1, col. 1). In our series of samples, mean stage of incubation in days subtracted from mean date of set-collection provided an estimate of date of clutch com- pletion. Unincubated ("fresh") eggs were included in the analysis of clutch size, after testing to determine if fresh sets might be biased by the collection of incomplete clutches. When sets of fresh eggs were separately compared with those of later incubation (t-test), no significant differences in clutch size were found (P > 0.05, Table 1). There remains the possibility that some egg collectors sought larger clutches. Calculations and Indices.All data were analyzed with an IBM 1620 computer. Sta- tistical analyses followed Steel and Torrie (1960). A size index for eggs was calculated by multiplying length by breadth and was used as a crude index to volume. In a study of White Pelicans (P. erythrorhynchos) (D. W. Anderson and J. J. Hickey, unpublished), we have found displaced volume to be correlated with this size index (P < 0.001). Geographical variations in egg size, shell thickness, shell weight, clutch size, and egg dates were determined in a stepwise manner as follows: (1) current subspecific range boundaries were determined from the AOU Check-list (1957) and Palmer (1962:275), and the range was then subdivided into small geographic units such as a single state; (2) the eggshell data for these were then tested for significant differences and regrouped until a region was obtained containing a maximum number of subunits that were not significantly different from each other; (3) groupings never included more than one March 1970 16 THE WILSON BULLETIN VoL 82. No. 1 TABLE 2 GEOGRAPHICAL VARIATION IN EGGSHELLS OF NORTH AMERICAN BROWN PELICANS, 1879 TO 19431 Subspecies occ car car car car car cal cal West Fla., Baja So. Area Indies S.C. Ca. La. Panama Texas Calif. Calif. Number 6 43 208 42 7 115 174 85 Wt. (g) 8.05 9.46 9.78 9.87 9.94 10.00 10.99 10.59 ___95% C.L. ___0.90 ___0.35 ___0.12 ___0.32 --+0.49 -+0.26 -+0.18 -+0.24 Size Index (cm '2) 33.2 37.6 37.6 38.2 37.4 38.5 40.0 39.0 -+95% C.L. -+0.6 -+0.9 -+0.3 -+0.7 -+1.0 -+0.6 -+0.4 -+0.7 No. Subelliptical 3 21 109 20 2 52 94 44 No. Oval 3 22 99 22 5 63 80 41 Thickness Index 2 2.42 2.52 2.60 2.58 2.66 2.59 2.74 2.71 -+95% C.L. +--0.24 -+0.06 -+0.02 -+0.06 -+0.10 -+0.04 -+0.02 -+0.04 Number 6 23 172 24 -- 43 83 28 Thickness (mm) 0.510 0.557 0.557 0.554 -- 0.557 0.569 0.579 -+95% C.L. -+0.031 -+0.021 -+0.004 -+0.014 -- -+0.012 -+0.008 -+0.014 1 The pre-1943 means that were not significantly different at the 95'% level in Duncan's New Multiple Range Test (Steel and Torrie, 1960:107-109, 114) are nnderscored. 2 From Ratcliffe (1967): Thickness in&ex = 10 X wt. in g/(length X breadth in cm). described subspecies; and (4) phenological subdivisions were kept at the smaller units without regrouping. RESULTS AND DISCUSSION Geographical Variation in Egg Parameters.--Egg.size index, shell weight, and shell thickness (Table 2) tended to vary with the size of the bird as discussed by Romanoff and Romanoff (1949:150). Our index to body size was obtained by using two common standard measurements that tend to measure skeletal size (tarsus and culmen) (Fig. 1). These skeletal measure- ments were taken from Wetmore (1945) and represent those of female birds. Wetmore (1945) ranked the size of the three North American subspecies, from largest to smallest as follows: P. o.. cali]o.rnicus, P.o. carolinensis, and P. o,. occidentalis. The general shape categories (Table 2) were, nonetheless, not significantly different (P > 0.05, Chi-square test) from area to area or between sub- species. Ordinary shape changes in the eggs of domestic poultry have already been shown to have little effect on the shell present as a percentage of total egg weight (Asmundson and Baker, 1940). Of the subspecies carolinensis, birds from Texas tended to have the largest Anderson and Hickey BROWN PELICAN EGG AND BREEDING DATA ]7 40 x 38 z N e 34 I i I I 18 20 22 24 (TARSUS XCULMEN)/1000 12 Fro. 1. Relationship between two egg measurements and index to body size in three subspecies of Brown Pelicans. The index to body size was calculated in mm 2 units and is shown on the abscissa. Eggshell size was taken as the product of length and breadth in cm". eggs. Louisiana eggs tended to be intermediate between those from Texas and those from areas to the east (Table 2). South Carolina birds tended to have smaller and lighter-shelled eggs than birds from farther south in Florida and Georgia, although not significantly so (Table 2). The Baja California eggs (P.o. cali/ornicus) were represented mostly by specimens from Los Coronados Island but suggested a similar gradient, with egg size decreasing from southern to northern colonies. Lack (1968:279) mentioned this trend among certain congenerics in certain tropical Procellariiformes. A con- tinuum in egg size and shell weight between different populations from different areas was suggested in our specimens, especially in carolinensis, although shell thickness in the various subspecies seemed relatively stable. Whether or not the intrasubspecific tendencies are genetic is unknown. They are likely genetic, but standard measurements from museum skins are needed for further comparisons. The intersubspecific variations in egg size are most likely representative of body size (Fig. 1). If one assumes that egg size provides an index to body size, the large Texas birds may represent an intermediate between c'alifornicus and carolinensis. Brown Pelicans along the Pacific Coast (californicus) have the larger and thicker-shelled eggs (Table 2). Asmundson et al. (1943) showed that larger eggs in several species tended to have the thicker shells, but the essentially March 1970 18 THE WILSON BULLETIN Vol. 82, No. 1 equal thicknesses from all our Gulf and Atlantic Coast eggs suggested that this relationship was not present on an intrasubspecific basis.. The small sample of eggs from Panama suggested that these eggs were most similar to the subspecies carolinensis, as Wetmore (1945) has shown with museum skins. Unfortunately, we were unable to obtain egg measurements from Ecuadorian or Peruvian Brown Pelicans. Murphy (1936:820) reported that the Peruvian pelicans are very large and we suspect that their eggs would also be larger and thicker-shelled. The ecological significance of egg-size difference within a species is largely a matter of speculation. Lack (1966:7) suggests that egg-size differences between different species (and larger groups) are mainly a matter of heredity. The differences we observed on an intersubspecific basis in Brown Pelicans at least implied that these eggs are represented by relatively distinct gene-pools. Perhaps such gene-pools are even distinct on an intrasubspecific basis. Mason (1945) showed that Florida Brown Pelican movements, at least, are some- what restricted under normal circumstances, suggesting potential isolation between breeding groups. Welty (1962:408 quoting Murphy, 1936) also suggests that this species is potentially sensitive to isolating barriers. Possible Factors for Bias.--It is not our primary objective here to specu- late on taxonomic relationships on the basis of eggs; nonetheless, the varia- tions in eggs are expected to relate in some ways to taxonomic characters (Tyler, 1964, 1965). Our interest is mainly to examine natural variation in order to better understand if unnatural change has occurred. Egg size and shell thickness and composition are known to vary with heredity, age, adult physiological condition, diet, and chemical influence (Romanoff and Romanoff, 1949:152-157, 359; Preston, 1958; Sturkie, 1965: 464, 487-488; Simkiss, 1967:157-197). Shell thickness also varies in dif- ferent areas of the egg of a given species, the most notable examples probably being the rock-nesting murres (Uria sp.) and other seabirds, where thickness tends to increase at the most vulnerable parts (Tuck, 1960:25). Some inter- specific differences in thickness have been shown to be related to the hazards associated with placement on different nesting substrates (Belopol'skii, 1957: 133-134). Fortunately, egg collectors drilled their specimens at the girths, the most uniform area for most species (Romanoff and Romanoff, 1949: 157-158). Shell calcium (about 5 per cent) is utilized, as well, by developing embryos (Simkiss, 1967:198-213); hence, shell weight and also possibly thickness may be biased low if eggs of late-stage incubation are used in the shell-thick- ness or weight comparisons. Data combined into carolinensis and cali- fornicus categories indicated this trend (Table 3), although not significant statistically (t-test, P > 0.05) and only amounting to a small percentage Anderson and Hickey BROWN PELICAN EGG AND BREEDING DATA 19 TABLE 3 SIIELL WEIGHTS OF PaE-1943 EGGS Or TWO SUBSPECIES OF Bm)WN PELICAN AT DIFFERENT INCUBATION STAGES Subspecies Mean 95% Incubation Stage No. Wt. (g) C.L. carolinensis First egg-3 days 98 9.75 0.21 412 days 230 9.88 0.14 13-21 days 53 9.76 0.28 cali/ornicus First egg-3 days 92 10.75 0.20 4-12 days 121 10.97 0.25 13-21 days 30 10.59 0.40 Both First egg-3 days 190 10.23 0.16 4-12 days 351 10.26 0.14 13-21 days 83 10.06 0.24 in our sample (1-3 per cent). Therefore, we do not believe this bias to be important in the oological data examined here. Furthermore, the data sug- gested that most egg collectors tended to collect eggs that were about one- third or less incubated (Table 1), thus eggs in late-stage incubation repre- sented a small percentage of our sample. Although effects on the egg stemming from the age and physiology of the laying female would remain undetectable in oological samples, they would not be expected to affect an overall random, or essentially random, sample (see Asmundson et al., 1943). Eggshell Changes and Pesticide Residues.The small samples of post-1949 specimens suggested thinning in all eggshells measured (Table 4). Florida specimens showed a -17 per cent change in shell weight, Texas specimens a -20 per cent change, California specimens (Anacapa Is.) a -26 per cent change, and one set of eggs from Panama a -15 per cent change. All were significant (P < 0.05) changes. We could detect no change in shape in these post-1949 eggs (P > 0.05, Chi-square test). The incubation stages were essentially the same for both pre-1943 and post-1949 eggs (6 -4- 2 days vs. 9 -4- 5 days, 95 per cent C.L.). Size indices were not significantly different (P > 0.05), although the post-1949 eggs from Texas and Florida were slightly smaller in mean than those of pre-1943. Whether or not these changes in weight and thickness were associated with either recent declines of the Brown Pelican or environmental pollution, or both, remains to be determined. Stickel (1968) has. stated that in Gulf Coast Brown Pelicans, pesticide residues were of approximately the same general magnitude as those of herons 20 THE WILSON BULLETIN March 1970 Vol. 82, No. 1 TABLE 4 POST-1949 EGGSHELL MEASUREMENTS OF BROWN PELICANS 1 Subspecies carolinensis carolinensis carolinensis calffornicus Area Florida Texas Panama California Number 9 6 3 9 Wt. (g) 8.10 7.96 8.45 7.89 ___95% C.L. ___0.14 ___0.60 ___0.99 ___0.66 Size Index (cm 2) 36.5 37.6 37.6 39.0 ___95% C.L. ___0.9 ___2.4 ___2.0 ___1.4 No. Subelliptical 1 2 2 7 No. Oval 8 4 1 2 Thickness Index 2 2.22 2.12 2.25 2.02 ___95% C.L. ___0.09 ___0.10 ___0.22 ___0.12 Number -- -- 3 9 Thickness (mm) -- -- 0.457 0.424 ___95% C.L. -- -- ___0.012 ___0.018 Post-'49 eggs were collected as follows: Florida--1950, 1953; Texas--1951; Panama--1952; Califonfia--1962. From Ratcliffe (1967): Thickness index = 10 X wt. in g/(length X breadth in cm). (Ardea cinerea) from Great Britain and Bald Eagles (Haliaeetus leucocepha- lus) in the United States (see Stickel et at., 1966; and Moore and Walker, 1964). Risebrough et at. (1967) analyzing two Brown Pelican eggs from the Gulf of California found them to be generally "low" in pesticide content (0.7 ppm [wet-weight basis] DDT and metabolites and about one-fifth as much potychtorinated biphenyts [PCB's], an industrial pollutant; endriM and dieldrin were also identified). They found an average of 0.8 ppm DDT- family residues (61 per cent DDE) and about two-thirds as much PCB in six Brown Pelican eggs taken in Panama. We converted the above residues to a ppm wet-weight basis by assuming 7 per cent fat in the eggs. We measured two of the eggshells from Risebrough's study (Baja California specimens) and found one suggestive of a "normal" egg (11.7 g, 0.59 mm in thickness) and the other suggestive of thinning (9.3 g, 0.50 nun). Another study (Anderson et at., 1969) showed that egg residues as low as 1 ppm of DDE, and possibly less, could be associated (P < 0.05) with detectable shell changes in White Pelicans, although egg residues may not always necessarily reflect residues in adults that could influence egg-shell deposition. Risebrough et at. (1967) reported 84.4 ppm of DDT-type residues, 91 per cent of which was p,p'-DDE (77 ppm) in the breast muscle of a Brown Pelican collected in California. These levels are only slightly lower than those reported from Lake Michigan Herring Gulls (Larus argentatus), which averaged 80 ppm DDE in the breast of adult birds (Hickey et at., 1966). Reproduction in the Anderson and Hickey BROWN PELICAN EGG AND BREEDING DATA 21 TABLE 5 MEAN DATES OF CIUTCH COMPLETION IN BaOWN PELICANS FROM VARIOUS GEOGRAPHICAL AREAS No. Mean Mean Area Clutches Date -4- s.r,. Stage Incubationl So. California 29 8 April q- 16 days 1.4 No. Baja California 61 10 April q- 54 days 1.8 Texas 36 9 May 4- 18 days 1.5 Louisiana 14 27 April 4. 31 days 1.6 Florida 75 29 May 4. 125 days 1.9 South Carolina 14 5 June q- 17 days 1.7 1 IXTumerically coded with TabLe 1, cols. 1-2. Wisconsin Herring Gull population in Green Bay (characterized by egg- breakage) is known to be severely affected by DDE and other residues (Keith, 1966; and Hickey and Anderson, 1968). Egg residues from the same population averaged 183 ppm DDE in 1963 and 1964 (Keith, 1966). Breeding Characteristics.--Pacific Coast data suggested that between north- ern Baja California and California, the breeding dates were somewhat closely related (Table 5). Gulf and Atlantic Coast birds, on the other hand, showed much variation, especially in Florida (Appendix 1) as discussed by Bent (1922:295) and Palmer (1962:277). Palmer's (1962:275) distribution map suggests that on the Pacific Coast, the major breeding populations of cali/ornicus are concentrated into a smaller area than those from Gulf and Atlantic Coast sites (carolinensis). Bent (1922:296), Howell (1932:85-87), and Lowery (1960:113-114) noted that Brown Pelicans of the subspecies carolinensis tended to utilize trees as well as coastal beaches and islands as nesting substrates. Murphy (1936:810-814) mentioned diverse breeding sites for South American pelicans as well. The Brown Pelicans of northern Baja California and California seem more generally restricted to ground- nesting on islands (Bent 1922:301; Williams, 1927). Bond (1942) reported tree-nesting for the California Brown Pelican as very unusual. In Florida, where the Brown Pelican still persists (Williams and Martin, 1969), a long breeding season and diversity of nesting substrate seem to char- acterize breeding. They nest year-round in Peru, although considerable shift- ing of sites occurs (Murphy, 1936:821822). The Gulf of California Brown Pelicans still persist as breeders, although there is no evidence of a longer breeding season than in colonies farther north (R. W. Risebrough, pers. comm.). Clutch sizes showed no significant variation (P > 0.05) between any of the geographical areas listed in Table 2. The means, and our best estimates. for clutch-size in the Brown Pelican, are given in Table 1. Bent (1922:297) March 1970 22 THE WILSON BULLETIN VoX. 82, No. 1 and Pahner (1962:277) stated that three eggs, and less often two, is the normal clutch size; nests with four and five eggs have been found. Breeding Records.--The population estimates by egg collectors cited in Appendix I must be viewed cautiously. These estimates were subject to observer error; however, they can provide an approximation of changes that might have occurred. Data-slip information, although most likely sketchy, can also provide documentation of past breeding locations. The records we found in egg collections did not provide a complete picture of breeding lo- calities but suggested possible fluctuations in numbers over the years (Appen- dix 1). On the other hand, none of the major colonies. seem to have been completely without birds since at least the late 1800's. Numbers probably increased on Anacapa Island, California, during the late 1920's. Williams (1927) reported a colony as far north as Point Lobos, California, during this time. The late 1920's may represent a period of population increase. Bond (1942) reported the estimated numbers on Anacapa Island from 1898 to 1941 to be highly fluctuating (estimates ran from about 200 to at least 2000 pairs). Banks (1966) reported eggs and young on Anacapa and essentially "normal" numbers of breeding birds, at least in 1963 and 1964, two years after the thin-shelled eggs reported here. The Los Coronados birds seem historically more stable (Appendix 1). It is certain that both Anacapa and Los Coronados breeders were historically present in large numbers (Banks, 1966). Risebrough (1968) and Schreiber and DeLong (1969) suggested that the Brown Pelican has decreased considerably in recent years off Cali- fornia, including no known breeders on Los Coronados in 1968. Perhaps the -20 to -26 per cent figure in shell change represents or approaches the lower limit to which eggs may survive to be collected by egg-collectors. Certainly, some production occurred in the California colony with these shell- changes, although present numbers suggest a declining population. Lowery (19'60:113-114) mentions large colonies in Louisiana; yet Winckler (1968), in a popular article, summarized their nearly virtual disappearance from the Gulf Coast by 1968. In the light of the better-known demise of Gulf Coast Brown Pelicans., we believe the status of California Brown Pelicans and populations farther to the south needs immediate study. ACKNOWLEDGMENTS This study was carried out as part of a contract with the Bureau of Sport Fisheries and Wildlife, Fish and Wildlife Service, U.S. Department of the Interior, Patuxent Wildlife Research Center, Laurel, Maryland. We are grateful to the many curators of museum collections listed in Appendix 1. The private collectors cited in Appendix 1 were extremely cooperative. We are especially grateful to Ed N. Harrison and Wilson C. Hanna for their personal assistance and extremely helpful suggestions. Mr. Harrison, in addition, located our 1962 samples of California eggs. Lucille F. Stickel and Eugene H. Dustman provided critical advice, and Ralph W. Schreiber suggested the immediate consolidation of our Brown Pelican data. Mrs. Pearl Davis punched our data cards, and the College of Agricultural and Life Sciences, University of Wisconsin, provided computer facilities at no cost. We are grateful to J. O. Keith and R. W. Risebrough for critical advice on the manuscript. APPENDIX ]_ BROWN PELICAN BREEDING RECORDS TAKEN FROhi NORTH AMERICAN OOLOGICAL RECORDS AND COLLECTIONS. Estimated Numbers; Museum * Date Location Remarks Observer of record Southern CaliJornia 27 May 1893 Anacapa Is. -- A.H. Miller 2 5 June 1910 Anacapa Is. 500-t- pairs G. Willett 3,5 7 Mar. 1916 Anacapa Is. -- M.C. Badger 2 2 Mar. 1917 Anacapa Is. -- M.C. Badger 3 15 May 1919 Anacapa Is. -- -- 1 7 Mar. 1920 Anacapa Is. 5,000+ pairs S.B. Peyton 30 8 Mar. 1922 Anacapa Is. -- S.B. Peyton 5 28 Mar. 1927 Anacapa Is. -- -- 3 24 Feb. 1929 Anacapa Is. -- C.W. Ashworth 2 1 Mar. 1936 Anacapa Is. -- E. Harrison 3 I Mar. 1936 Anacapa Is. 2,000-k pairs L.T. Stevens 14 12 Mar. 1939 Anacapa Is. "large colony" L.T. Stevens 4,7 19 May 1919 San Miguel Is. -- -- 1 25 May 1927 Point Lobos 8-10 nests L. Williams (1927) 2 Baja Cali/ornia, Mexico 18 Apr. 1894 Los Coronados -- E. Parker 27 19 Apr. 1894 Los Coronados -- -- 1 4 Apr. 1895 Los Coronados -- A. Hewitt 2,22 19 Apr. 1898 Los Coronados -- A.J. Kellog 24 27 Apr. 1898 Los Coronados -- -- 3 6 May 1904 Los Coronados -- O.C. Polling 2 6 Apr. 1908 Los Coronados 500 nests P.I. Osborne 1,4 March 1970 THE WILSON BULLETIN Vo. 82, No. I 24 (APPENDIX 1 CONTINUED) Estimated Numbers; Museum* Date Location Remarks Observer of record 6 Apr. 1908 Los Coronados -- A. Van Rossem 25 1 July 1908 Los Coronados -- P.I. Osborne 9 4 Apr. 1910 Los Coronados -- P.I. Osborne 29 2 Apr. 1912 Los Coronados -- C.S. Thompson 23 1 Apr. 1913 Los Coronados 500 nests L.M. Huey 3 29 Mar. 1914 Los Coronados -- W.C. Bradbury 2,9 31 May 1915 Los Coronados -- I.D. Nokes 5 26 Mar. 1917 Los Coronados 500 pairs N.K. Carpenter 6 4 May 1917 Los Coronados -- D.S. DeGroot 2 11 Apr. 1919 Los Coronados -- N.K. Carpenter 23 12 May 1921 Los Coronados -- W.C. Hanna 4 30 Mar. 1922 Los Coronados -- -- 1 15 Apr. 1881 Mexican coast -- -- 1 26 Mar. 1917 So. Coronados, SE slope -- -- 1 6 Apr. 1920 Todos Santos Is. -- G. Bancroft 4 6 Apr. 1920 Todos Santos Is. -- J. Burnham 26 17 Apr. 1921 San Pedro Nolasco Is. -- -- 1 2 May 1921 Granite Is. -- -- 1 7 Apr. 1932 San Benito Is. -- E. Harrison 3 10 Apr. 1932 San Martin Is. -- E. Harrison 3 2 June 1932 Asunci6n Is. -- E. Harrison 3 Panama 15 Feb. 1942 Chama Is., Panama Bay, Panama -- A. Wetmore 13 15 Mar. 1952 Taboga Is., Panama -- A. Wetmore 13 10 May 1886 Near Corpus Christi 20 May 1888 Neuces Co. 10 Apr. 1889 So. Bird Is., Laguna Madre 16 Apr. 1889 So. Bird Is., Laguna Madre 14 June 1894 25 mi. from Corpus Christi 14 May 1896 So. Bird Is., Laguna Madre 28 May 1910 Near Corpus Christi 30 May 1910 Near Corpus Christi 3 May 1912 Laguna Madre 18 May 1913 Neuces Co. 27 May 1915 Padre Is. 19 May 1917 Big Bird Is., Laguna Madre F. B. Armstrong 12 T. S. Gillin 4 J. A. Singley 2 J. A. Singley 4,25 F. B. Armstrong 1 D. B. Burrows 2 C. E. Farley 30 J. M. Carroll 4 J. M. Priour 4 F. B. Armstrong 9 F. B. Armstrong 2 R. W. Quillan 19 Anderson and Hickey BROWN PELICAN EGG AND BREEDING DATA 25 (APPENDIX I CONTINUED) Estimated Numbers; Museum* Date Location Remarks Observer of record May 1919 Is. off so. coast -- -- 3 15 May 1919 Laguna Madre -- H. Brandt 10 5 May 1922 Neuces Co. -- G. Stewart 11 24 May 1925. Pelican Is., Aransas Bay -- R.D. Camp 31 1951 Refugio Co. -- T.C. Meitzen 18 Louisiana 29 Mar. 1893 Lost Is. -- F.A. Mcllhenny 2 28 Mar. 1894 Marsh Is. -- F.A. McIlhenny 2 29 Mar. 1894 Shell Keys -- F.A. Mcllhenny 2,23 3 June 1919 Pass & l'Outre -- E.R. Kalmbach 13 5 June 1919 Errol Is. -- J.D. Figgins 9 26 May 1938 North Is. -- F. Tobin 10 13 Apr. 1940 La Fourche Par., G.H. Lowery Timbalier -- (1960) 17 Florida 15 Mar. 1879 Near Marco -- -- 1 1 Apr. 1880 Indian R. -- C.L. Gass 26 15 Apr. 1880 Indian R. -- -- 1 29 Apr. 1880 Old Tampa Bay -- -- 1 12 Apr. 1890 Lee Co. -- H.R. Jamison 4 12 Apr. 1890 Charlotte Harbor -- S. Reiff 21 3 May 1890 W. of Pine Is., Lee Co 225 nests N.K. Jamison 4 26 Apr. 1891 Pelican Is. -- M. Gibbs (1894) 9 12 Apr. 1892 Tampa Bay -- D.P. Ingraham 27 10 May 1893 Pelican Is. -- J.M. Southwick 4 5 June 1893 Mullett Key -- B.T. Smith 26 30 June 1894 Tampa Bay -- -- 1 21 Jan. 1896 Pelican Is. 500. pairs B.W. Evermann 23 3 Apr. 1896 Pelican Is. -- H.E. Pendry 3 30 Apr. 1896 Seminole Is. -- H.E. Pendry 5 18 May 1896 Rookery Is., off Diston City -- W. Meyor 8 15 May 1899 Brevard Co. -- F.S. Webster 10 19 Apr. 1908 Boca Grande, Charlotte Keys 200 birds P.B. Phillipp 12 20 Apr. 1908 Charlotte Harbor, Devilfish Key -- P.B. Phillipp 12 3 May 1911 Pelican Is. -- P.B. Phillipp 12 19 May 1911 Hillsborough Co. -- O.E. Baynard 24 27 Apr. 1913 Lee Co. -- O.E. Baynard 3,9 27 Apr. 1913 Roco Bay, Pinellas large colony O.E. Baynard 8 Co. in trees 26 THE WILSON BULLETIN March 1970 Vol. 82, No. 1 (APPENDIX 1 CONTINUED) Estimated Nunlbers; Museum* Date Location Remarks Observer of record 15 May 1918 Tampa Bay -- 20 Apr. 1920 Tampa Bay -- 17 May 1921 Tampa Bay -- 17 May 1921 Tampa Bay -- 27 May 1921 Tampa Bay -- 28 Dec. 1921 Pelican Is. -- 20 Apr. 1926 Pinelias Co. -- 1 June 1926 Merritt Is. -- 10 June 1929 Merritt Is. 2,500 pairs 28 Mar. 1930 Lee Co. -- 25 Apr. 1930 Near Bokelia? -- 10 Apr. 1931 Mosquito Lagoon, Brevard Co. 2,000-4- nests 6 June 1931 Pine Is. Res., Bird Key -- 7 June 1931 Matlacha Pass Res., 6-mi. Is. -- 3 May 1932 Bird Key, Hillsborough 22 Apr. 1934 Rattlesnake Key, Levy Co. -- 9 Mar. 1950 Is., n. side of Cocoa-- Cocoa Beach 375 nests 10 Mar. 1953 Merritt Is. -- J. L. Vaughn 4 -- 3 J. L. Vaughn 2,20 W. F. Lewis 8 J. L. Vaughn 23 T. D. Burleigh 10 C. E. Doe 16 K. Squires 2 J. C. Howell, Jr. 12 C. E. Doe 16 C. E. Doe 16 W. H. Nicholson 23 R. W. Williams 13 R. W. Williams 13 R. E. Gammell 7 C. E. Doe 16 C. E. Carter 15 H. Brandt 10 Georgia 16 June 1898 Chatham Co. on beach T.D. Perry 1,16 South Carolina 10 May 1901 Bird Bank, Bull's Bay -- 20 June 1901 Near Charleston on beach 23 June 1901 Bay Point, near Beaufort "large colony" 23 May 1915 Bird Bank, Bull's Bay -- 18 June 1915 Bird Bank, Bull's Bay -- 7 July 1916 Bull's Bay -- 3 June 1925 Bull's Bay -- 14 June 1934 Georgetown Co. -- 20 June 1942 Bull's Bay -- 10 June 1943 St. Helens Sound, Beaufort (Bird Bank) -- 10 July 1943 18 nil. e. Beaufort -- Cuba 8 Sep. 1930 Cacachita Bay -- P. Bartsch 13 M. T. Cleckley 9 -- 3 M. T. Cleckley 3 A. C. Bent 13 A. Sprunt, Jr. 30 M. T. Cleckley 28 W. B. Savary 5 H. L. Hurllee 14 E. J. DeCamps 14 E. J. DeCamps 4 E. J. DeCamps 14 * Museums and collections are numbered as follows: 1. Calif. Acad. Sci., San Francisco; 2. Mus. Vert. Zoo[, Univ. Calif., Berkeley; $. Western Found. Vert. Zool., Los Angeles, Calif.; 4. San Bernardino Co. Mus., San Bernardino, Calif.; 5. S. B. Peyton, private collection, Fillmore, Calif.; t3. Oakland Publ. Mus., Oakland, Calif.; 7. Santa Barbara Mus. Nat. Hist., Santa Barbara, Anderson and Hickey BROWN PELICAN EGG AND BREEDING DATA 27 Calif.; 8. San Diego Mus. Nat. Hist., San Diego, Calif.; 9. Denver Mus. Nat. Hist., Denver, Col().; 10. Carnegie Mus., Pittsburgh, Pa.; 11. Philadelphia Acad. Sci., Philadelphia, Pa.; 12. Amer. Mus. Nat. Hist., New York, N.Y.; 13. U.S. Natl. Mus., Wash., D.C.; 14. Zoological Mus., Clemson Univ., Clemson, S.C.; 15. C. E. Carter, private col,ection, Orlando, Fla.; 16. Fla. State Mus., Gaines- ville; 17. L.S.U. Mus. Nat. Sci., Baton Rouge, La.; 18. T. C. Meitzen, private collection, Refugio, Tex.; 19. R. W. Quillan, private collection, San Antonio, Tex.; 20. Univ. Kans. Mus. Nat. Hist., Lawrence; 21. Univ. 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DEPARTMENT OF WILDLIFE ECOLOGY UNIVERSITY OF WISCONSIN MADISON 53706. 12 MAY 1969.