Monitoring of Nesting Emperor Geese on Kigigak Island, Alaska, 2018

BRYAN L. DANIELS, U.S. Fish and Wildlife Service, Yukon Delta National Wildlife Refuge, P.O. Box 346, Bethel, AK 99559

SUMMARY: The Emperor Goose ( canagicus) is an endemic goose of Alaska. Emperor geese winter along the Alaska Peninsula and , and breed primarily in the Yukon Delta National Wildlife Refuge (YDNWR). Beginning in the early 1980’s, aerial surveys documented a population decline that led to harvest restrictions and closures implemented in 1985. In 2016, surveys indicated the population reached a threshold allowing the reopening of Emperor goose harvest. With the opening of a hunting season, and an annual population growth rate of 2% over the previous 30 years without hunting, managers and biologists had concerns about the level of harvest the population could sustain, as well as the number of young being produced to sustain the breeding population at current levels. With the Yukon Delta being the primary breeding location for Emperor geese, YDNWR began monitoring clutch size, nest success, nest initiation dates, and adult survival of Emperor geese on Kigigak Island, YDNWR, Alaska. A total of 141 Emperor goose nests were monitored in 2018. Mean clutch size was similar to historic studies at 4.96 eggs in 2018 with a mean clutch size of 5.05 for the 2 years of this study. Apparent nest success was 70% in 2018 and nest predators were the highest cause of nest failure with 18% being depredated. Mean nest initiation date (13 May 2018) was 10 days earlier than recorded on the Yukon Delta from 1982-2016. With limited prior information on Emperor goose nest success on Kigigak Island, the results of this study will provide a baseline for future efforts while tracking individual marked goose survival and nest success.

(Data Submitted to BBL 27 September 2017; Report Completed February 2018)

KEYWORDS Emperor goose, Kigigak Island, nesting, nest success, nest initiation

INTRODUCTION Emperor geese are monogamous and have The Emperor Goose (Anser canagicus) is an high nest site fidelity (Shmutz et al. 1997), endemic goose of Alaska. Emperor geese returning to the same area to nest. Adult winter along the Alaska Peninsula and females are important for population Aleutian Islands, migrate in the spring and productivity and adult female survival is the fall along the coastal areas of the Alaska most sensitive demographic to population Peninsula and Yukon Delta, and breed growth (Shmutz et al. 1997). Studies of primarily along the coastal fringe of the waterfowl suggest that individuals’ lifetime Yukon-Kuskokwim Delta, Seward Peninsula, reproductive success varies within a and Russia (Peterson 1992, Pacific Flyway population (Raveling 1981, Owen and Black Council 2016). 1989), and although variation between

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 1 individuals exists, individual often lay probability of nesting in future years, and 3) similar clutch sizes and initiate laying at the band nesting female Emperor geese for same time each year (MacInnes and Dunn future mark-recapture analyses of adult 1988, Gauthier 1989, Peterson 1992). female survival. This is the second year of this study. Beginning in the early 1980’s, aerial surveys documented an Emperor goose population STUDY AREA decline that led to conservation concerns, resulting in fall/spring harvest closure for Kigigak Island (KI; 32.5 km2, 6050’N, sport and subsistence hunting beginning in 16550’W) was chosen as a study site 1985 (Pacific Flyway Council 2006). With because the island has a high density of these restrictions, the population grew at nesting Emperor geese near an already 2% per year (Pacific Flyway Council 2016). established remote field camp. Kigigak In 2016, aerial surveys indicated the Island has a maximal elevation of 1-3 m population reached a threshold that would above sea level, and is situated northwest allow the re-opening of Emperor goose of Nelson Island and 20.5 km west of the harvest as outlined in the Pacific Flyway village of Newtok on the Yukon Delta Emperor Goose Management Plan (Pacific (Solovyeva et al. 2017). Bordered by the Flyway Council 2016). Because majority of Ninglick River and the , the island the Emperor goose population nests on the exhibits diverse habitats in a small area, Yukon Delta (Eisenhauer and Kirkpatrick ranging from tidal sloughs extending into 1977) a spring subsistence hunting season the interior of the island, to grass uplands occurring just prior to nesting on the Yukon on the eastern part of the Island, and Delta would potentially have the greatest lowland tundra and pingos in the center of effect on population growth. With the the island. The preferred nest sites for opening of the subsistence hunt, managers Emperor geese include slough borders, and biologists had concerns about the grass meadows, pond shorelines, populations’ ability to maintain sustainable peninsulas, and ericaceous tundra harvest. (Kistchinski 1971, Mickelson 1975, Eisenhauer and Kirkpatrick 1977). To determine if the re-opening of the hunting seasons would reduce adult The YDNWR designed 1.28 km x 2.98 km survival (and potentially decrease plots across the entire island to search for population size), the Yukon Delta National emperor goose nests (Figure 1). Emperor Wildlife Refuge (YDNWR) began nest goose nest plots were selected based on monitoring and capture-mark-recapture densities of Emperor geese found during program on nesting female Emperor geese annual Spectacled Eider (Somateria Fischeri) on Kigigak Island, YDNWR in 2017. The nest plot surveys and coastal zone aerial objectives of this study were to: 1) monitor surveys from 1985-2016 (Figures 2 and 3, Emperor goose nests for success and Fischer personal communication). These individual variation, 2) gather plots were between 0 and 2.4 km away morphometric data on nesting female from camp, making searching and trapping Emperor geese to determine if female efforts for nesting Emperor geese efficient. goose size influences clutch size or

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 2 METHODS recorded to the nearest thousandth. The goose’s mass (kg) was obtained by placing Data Collection the in a pillow case attached to a hanging scale. All capture data was Nest Searching recorded on the capture data sheet Plots were searched thoroughly by foot by (Appendix B). After the bird was released, 1-2 people over a 12-hour period. five contour feathers were collected from Observers utilized binoculars to aid in within the nest bowl for future stable detection of nesting Emperor geese, then isotope analysis, eggs were replaced, and data was collected at Emperor goose nests. the nest was covered with down to protect from aerial predators. Nest cards showing data collected at each nest can be found in Appendix A. Eggs were Nest Fates individually marked with a sharpie to detect Between one and 4 days after hatch, if new eggs were laid or removed during observers returned to the nest to subsequent visits. For each nest, three eggs determine nest fate. A nest was considered were aged via candling and floating successful if ≥ 1 eggs hatched as evidenced methods to predict expected hatch date. All by presence of a membrane. nests were marked with a flag placed three meters north with the nest ID. Data Analysis

Trapping and Banding We used simple proportions of successful Nesting female geese were trapped in late nests (apparent nest success) for analysis stage incubation (last 4 days), to minimize because of the relative synchrony of probability of abandonment (Peterson Emperor goose nesting, the high probability 1992). When nests were nearing the final 4 of finding nests, and the nest visitation predicted days of incubation, a minimum of schedules used (Johnson and Shaffer 1990). two people returned to the nest to flush the goose and update the nest card to ensure Growth of geese is highly correlated with egg age prediction was correct from the the quality and quantity of forage during previous visit. If the nest was within 4 days brood rearing (Sedinger et al. 1997). Given of hatch, traps were set and incubated eggs that growth at a young age may have were swapped with 2-3 fake eggs to negative consequences to fecundity (Owen minimize probability of eggs being broken and Black 1989), we used ANOVA to test if during trapping. difference in size of adult female could predict difference in clutch sizes within a After the goose was captured and removed year. from the bownet, the bander recorded the band number and affixed the size 7B All parameters are reported as mean ± 1 SE. stainless steel band on the bird’s right leg. The 3-coded, black on turquoise plastic Data is stored on YDNWR share drive at: auxiliary band was affixed on the left leg. T:\Data\Share\Biology Program Using calipers, the total tarsus, total head, 2018\Waterfowl project and culmen length (cm) were measured and planning\Kigigak\Data\working_emgo2.csv

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 3 length of 3.63 ± 0.02 cm (n = 143), and And Tarsus length of 7.79 ± 0.03 cm (n = 147; Table 2). T:\Data\Share\Biology Program 2018\Waterfowl project Clutch size could not be predicted by head planning\Kigigak\Data\ 2018 morphometic length (ANOVA F139= 0.004, P = 0.95), modelling.csv culmen length (ANOVA; F139 = 2.254, P = 0.14), Tarsus length (ANOVA; F139 =1.12, P = RESULTS 0.29, Figure 6), or mass at time of capture (ANOVA; F128 = 0.008, P = 0.93). Primary nest searching occurred for five days from 23 - 29 May 2018 and a There is no evidence that head length secondary nest search 1 - 5 June 2018. (GLM; F1 = 0.04, P = 0.51), tarsal length Trapping females on nests began on 1 June (GLM; F1 = 1.03, P = 0.31), or clutch size 2018, and ended on 19 June 2018. (GLM; F1 = 0.005, P = 0.94) has any influence on nesting success. In 2018, 148 Emperor goose nests were found and monitored in 11 plots. Of the 148 In 2017, 86 female Emperor geese were nests, 141 were monitored until hatch or banded (Daniels and Friendly 2018). In failure (Table 1). Of the 141 nests 2018, 29 of the 86 banded Emperor geese monitored, apparent nest success was 70% were observed alive within our plots (34%). (n = 103), 18% (27 nests) were depredated, Of the 29 observed, 28 of the bands were and 7% (n = 11) were abandoned. read by observers for future survival analyses (Table 3). After removing 7 nests that contained obvious eggs laid by other species or Head length (ANOVA; F1= 3.604, P = 0.06), individuals based on incubation stage, mean tarsus length (ANOVA; F1= 0.322, P = 0.57), clutch size was 4.96 ± 0.15 eggs in 2018 (n = 2017 clutch size (ANOVA; F1= 1.15, P = 139; Figure 4), and a mean clutch size of 0.29), and 2017 nest success (ANOVA; F2= 5.05 ± 0.11 eggs for the duration of this 1.10, P = 0.33) were not significantly study. Mean nest initiation date was 13 different between birds that returned and May 2018 (Figure 5). Peak nesting ended on nested in 2018 from the 86 marked May 20. Earliest nest initiation date was 24 individuals from 2017. April, and latest initiation date was likely a re-nesting attempt on 6 June 2017. DISCUSSION

Of 71 nesting female Emperor geese Nest success was lower in 2018 than 2017 captured and banded, a subset of (70% vs 81%; Daniels and Friendly 2018), morphometric measurements were taken and lower than nest success in the 1970’s from all individuals. Mean mass (at capture) (82% success; Mickelson 1975), but similar of nesting female Emperor geese captured to nest success in the 1980’s (72% - 90%; during this study in 2017 and 2018 was 1.68 Peterson 1992). Nest depredation was ± 0.01 kg (n = 130), with a mean head similar between the 2 years of this study length of 9.35 ± 0.02 cm (n = 143), Culmen (18% vs 17%). At least 1 fox and 1 pair of

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 4 pomarine jaegers were known to be on the Mean clutch size on Kigigak Island in 2017 island during 2017 season, and 1 red fox and 2018 was similar to birds nesting on the (Vulpes vulpes), 2 arctic foxes (Vulpes Yukon Delta in the early 1980s (5 eggs; lagopus), 2 pairs of Pomarine jaegers Peterson 1992, Thompson and Raveling (Stercorarius pomarinus) were seen 1987), but larger than in the late 1970’s (4 regularly in the study area in 2018, which eggs; Mickelson 1975). Exhibiting a similar are known to depredate unattended nests. clutch size lends us to believe individual Alternate prey (Microtus spp.) were more health of geese has not changed, and abundant in 2018 than 2017, which may wintering and spring staging food resources have been an initial attractant of more are sufficient to provide energetic resources jaegers to the island. No fox kits were seen required for nesting, being that Emperor during the study period, so it is assumed geese rely heavily on body reserves adults were unsuccessful at breeding, and acquired during winter and spring for clutch had more time to search for and cache formation and incubation (Ankney and eggs. Maclnnes 1978).

Nest abandonment was greater in 2018 Timing of waterfowl nest initiation is than 2017 (7% vs 2%; Daniels and Friendly correlated with timing of spring breakup 2018), which may be attributed to (Raveling 1978, Dau and Mickelson 1979), increased researcher disturbance across the which has been earlier each year on the study area in 2018. Only one nest was Yukon Delta. Mean nest initiation date for abandoned after initial nest checks during Emperor geese in 2018 was 11 days earlier egg laying, and 10 nests were abandoned (13 May 2018 ) than mean initiation date after trapping or attempting to trap the between 1985 and 2016 (24 May; Fischer et female at late stage incubation (>20 days of al 2017). Geese typically have arrived as incubation). We attempt capture near end snow melted and initiated as nesting sites of incubation to limit probability of became available (Peterson 1992), but with abandonment, but abandonment was warmer springs and less snow cover, birds higher than expected in 2018. Some of the are arriving to the breeding grounds sooner, nests were also partially depredated, and initiating nests when conditions are perhaps due to a combination of trapping favorable. Emperor geese were seen on the efforts and females being absent from the island on 2 May by another research team, nest for too long, allowing predators to get and they found the first Emperor goose nest to the nest that ultimately led to on May 9 with eggs. It is unknown which abandonment. Increased disturbance, and environmental cues prompt emperor geese associated probability of depredation (Esler nest initiation. and Grand 1993) in 2018 likely occurred because researchers were visiting the plots Individual goose size was not a predictor of daily for goose capture attempts due to clutch size in 2017 or 2018. Nesting high nesting densities, as well as conducting probability for many arctic nesting geese is a secondary study on nesting bird behavior linked to individual quality and body in relation to Unmanned Aerial Systems condition (Sedinger et al 2008, Williams (drones). 1966; Charnov & Krebs 1974). In Barnacle geese (Branta leucopsis), larger individuals

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 5 had a higher probability of breeding year to nest, but varied among individuals successfully in any year and produced more in regards to frequency of returns. Because goslings than did smaller birds (Choudhury birds may have nested outside of our study et. al 1996). However, there was so little area and not detected, our detection rate variability in head and tarsal sizes between may be biased low. Similarly, Emperor individuals marked in 2017, we were unable geese are known to forego nesting in some to detect a significant difference in years, but still be alive and elsewhere, so morphological measurements between true survival estimates cannot be calculated marked geese detected in 2018 and those for our marked population yet, nor can that were not re-detected, which leads us probability of returning be calculated. to believe goose size in Emperor geese does not explain probability to nest in a given In 2018, one red fox and 2 arctic foxes were year. known to be present on the island. Both the red fox and arctic foxes were seen regularly Similarly, goose size (head length and tarsal in the study area, and were observed length) and clutch size had no explanatory attempting to depredate nests during power for nest success. We interpret this to capture attempts. When foxes were seen mean that larger Emperor geese do not lay during trapping, trap attempts were larger clutches, and are not more successful stopped, and foxes were watched until they within a given year. Other factors such as were out of the trap area. age (Finney and Cooke 1978, Raveling 1981) or climate (Dickey et al. 2008) may be a As global climate change continues, warmer better explanatory variably for nest success. winters, earlier springs, and longer summers may create a mismatch in timing Although field crew arrived in the field after of nesting and vegetation growth for brood mean nest initiation, nest searching was not rearing. constrained. Field crew were able to locate 148 Emperor goose nests, and monitor 141 MANAGEMENT IMPLICATIONS until hatch. Although we cannot account for nests that were lost or abandoned in early With limited prior information on Emperor stages of incubation when most nests are goose nest success for Kigigak Island, the depredated (Peterson 1992) prior to our results from this study will be used as a arrival into the field, we do not think our baseline moving into the future while success rate is biased high (Mayfield 1961) tracking individual marked goose survival, due to the conspicuous nature of Emperor nesting frequency, and nest success. goose nest located on pond and slough edges in short vegetation, they could be ONGOING RESEARCH OBJECTIVES readily located, even if destroyed. We hope to determine if adult body size, Researchers detected 29 of 86 (33%) previous clutch size, previous nesting returning banded Emperor geese within status, and previous nesting success searched plots. This is lower, yet consistent explains some frequent non-nesting in with findings from Peterson 1992, where Emperor geese in future years. 38% -52% of marked geese returned every

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 6 ACKNOWLDGEMENTS

The success of this project would not have been possible without the hard work, patience and willingness to walk many miles of the waterfowl crew members, Heather Johnson, Mikaela Aroff, Jordan Thompson, and Christian Bartell. Thank you to YDNWR staff and USFWS aviation department for providing exceptional logistic support, especially pilots Mike Wade, Nate Olson, and Robert Sundown for exceptional aviation support. Thank you to Lewis Coggins and Gary Decossas for statistical help, and Lewis Coggins for reviewing reports. Finally, thanks to Joel Schmutz with USGS and Julian Fischer for guidance and recommendations during the planning of this project.

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 7

Table 1: Number of Emperor goose nests per plot monitored in 2018 on Kigigak Island, Yukon Delta National Wildlife Refuge.

Number Number of Number Number of Females Re-sighted Nests Number Unknown Plot nests Trapped Females Successful Nests Failed Nest Fate C6a 2 0 0 1 1 0 D5 19 12 0 11 6 2 D6 12 8 2 8 2 2 E4 18 11 1 12 5 1 E5 20 9 6 14 6 0 E6 31 14 8 21 9 1 E7 2 1 0 2 0 0 F4 7 2 1 7 0 0 F5 8 2 3 8 0 0 F6 28 12 8 19 8 1 G5a 1 1 0 0 1 0 Total 148 72 29 103 38 7 a These nests were found on edge of plots and entire plots were not searched. Density of nests should not be implied for these plots.

Table 2: Mean morphometric measurements of female Emperor geese caught during 2017 and 2018 nesting seasons on Kigigak Island, Yukon Delta National Wildlife Refuge, Alaska.

Head Culmen Tarsus Mass Length Length Length (kg) (cm) (cm) (cm) (n=130) (n=143) (n=143) (n = 147) Mean 1.68 9.35 3.63 7.79 SE 0.01 0.02 0.02 0.03

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 8 Table 3: List of 29 of 86 Emperor geese marked in 2017 that were re-sighted as nesting in 2018.

Band Number Tarsal Code 2017-15204 A00 2017-15208 A07 2017-15209 A08 2017-15223 A12 2017-15224 A13 2017-15226 A15 2017-15227 A16 2017-15232 A22 2017-15234 A25 2017-15235 A26 2017-15237 A28 2017-15211 A30 2017-15212 A31 2017-15213 A32 2017-15214 A33 2017-15216 A35 2017-15241 A40 2017-15250 A49 2017-15261 A50 2017-15262 A51 2017-15264 A53 2017-15268 A58 2017-15239 A60 2017-15270 A70 2017-15275 A75 2017-15256 A81 2017-15282 A95 2017-15285 A98

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 9

Figure 1: Emperor goose plots overlaid on Kigigak Island, Yukon Delta National Wildlife Refuge.

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 10 Kigigak Island

Figure 2: Emperor Goose concentrations based on nest plot surveys on the Yukon-Kuskokwim Delta between 1995 and 2016.

Kigigak Island

Figure 3: Emperor Goose concentrations based on aerial observations during coastal zone survey of the Yukon-Kuskokwim Delta between 1985 and 2016.

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 11

Figure 4: Number of eggs per clutch in 139 monitored Emperor goose nests in 2018 on Kigigak Island, YDNWR.

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 12

Figure 5: Initiation date frequency of Emperor goose nests in 2018 on Kigigak island, YDNWR. Mean nest initiation date of 134 (13 May 2018).

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 13

Figure 6: Median tarsal length (cm) of adult female Emperor geese with associated clutch size on Kigigak Island, Yukon Delta National Wildlife Refuge in 2017 and 2018.

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 14 Literature Cited

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USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 15 Canada Geese. Condor 90:83-89.

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USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 17 Appendix A: Emperor goose nest check data card.

YEAR: PLOT #: NEST#: SPECIES: EASTING: NORTHING: NEST SITE: Slougbank, Pondshore, Island, Displaced Island, Peninsula Pingo, Grassflat, Other On or Off RESIGHT: Resight? Y N Method: Visual/ Camera BAND # NASAL: TARSAL: FEATHERS: Collected: Y N # Collected: NEST VISIT:

NEW MISSING INV BROKEN ABAND UNK HEN NEST OBS DATE TIME EGGS EGGS EGGS EGGS EGGS EGGS F C STATUS STATUS COMMENTS

1)

2)

3)

4)

5)

6)

Key for front of nest searching data card Year Obs 201x Your initials Plot # When trapping also include partners initials Which plot is nest in? Date Nest # Date of nest visit Code each nest individually Time Typically use first initial of First, Middle, and Last name Start of nest visit followed by a number End of nest visit Ex. MLG001 Egg Status Species New Eggs – how many new eggs in nest/ number of EMGO- Emperor Goose eggs first visit Easting & Northing Missing Eggs – How many eggs are missing from Taken from GPS previous check Collected in UTM Inv Eggs – Inviable eggs Nest Site Broken Eggs – Please note whether it was from Description of nest location handling or from Flushed Female Sloughbank Aband – Abandoned eggs. Usually cold Pondshore Unk – Unknown status. This will be important at Island the end of the field season during final checks. Displaced Island But if you are unsure of an eggs status mark it as Peninsula unknown Pingo F Grassflat Floating angle Other – give description Float 2-3 eggs in the nest Is nest ON or OFF plot. C Circle one Candling angle Resight Candle 2-3 eggs in the nest Was the bird marked? Hen Status Were you able to read marker if so, How? (F) Flushed Visual – binoculars, scope (P) Present Camera (A) Absent Band # - will look it up Nest Status Nasal – do not use this space (I)Incubating Tarsal – what was code if read (A) Abandoned Feathers (H) Hatched Were feathers collected Yes or No (U) Unknown Circle one (L) Laying How many feathers were collected?

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 18

Appendix B: Emperor Goose capture data card.

BANDING/TRAPPING INFO YEAR: PLOT #: NEST#: SPECIES:

EASTING: NORTHING: TIME: Start of Trapping: End of Trapping: TRAP METHOD: Bownet Mistnet BANDING: Recapture/Resight? Y N BAND # NASAL: TARSAL: WEIGHT: TARSUS: CULMEN: FEATHERS: Collected: Y N # Collected: NEST CHECK: TOTAL NEW MISSING INVBL HEN NEST OBS DATE EGGS EGGS EGGS EGGS F1 C1 STATUS STATUS COMMENTS 1)

Key for back of nest searching data card Year Obs 201x Your initials Plot # When trapping also include partners initials Which plot is nest in? Date Nest # Date of nest visit Code each nest individually Egg Status Typically use first initial of First, Middle, and Last name Total eggs: number of eggs total in nest followed by a number New Eggs – how many new eggs in nest/ number of Ex. MLG001 eggs first visit Species Missing Eggs – How many eggs are missing from EMGO- Emperor Goose previous check Easting & Northing Inv Eggs – Inviable eggs Taken from GPS F Collected in UTM Floating angle Trap mehthod Float 2-3 eggs in the nest Circle one C Resight Candling angle Was the bird previously marked? Candle 2-3 eggs in the nest Band # - write metal band numbers Hen Status Nasal – Record total head length in cm (F) Flushed Tarsal – what was tarsal code if read (P) Present Weight: record mass in grams (A) Absent Tarsus: record total tarsus length in cm Culmen: record culmen length in cm Nest Status Feathers (I)Incubating Were feathers collected Yes or No (A) Abandoned Circle one (H) Hatched How many feathers were collected? (U) Unknown (L) Laying

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 19 Appendix C: Raw morphometric data from nesting female Emperor geese on Kigigak Island, Yukon Delta National Wildlife Refuge, 201 and 2018.

Head Culmen Tarsus Band Tarsal Nest # Catch date Mass (KG) length length length number Code (cm) (cm) (cm) 2017-15204 A00 JMK003 6/5/2017 1.79 9.55 3.76 7.68 2017-15205 A02 BLD027 6/5/2017 1.77 9.06 3.84 7.58 2017-15206 A04 BLD033 6/5/2017 1.69 9.27 3.73 7.39 2017-15207 A06 BLD032 6/5/2017 1.84 9.20 3.73 7.61 2017-15208 A07 BLD010 6/6/2017 8.07 2017-15209 A08 BLD017 6/6/2017 9.01 3.83 7.48 2017-15210 A09 GT019 6/6/2017 1.69 9.44 3.88 7.82 2017-15221 A10 GT023 6/5/2017 1.89 9.87 3.60 7.95 2017-15222 A11 RF031 6/5/2017 1.68 9.44 3.72 7.74 2017-15223 A12 RF035 6/6/2017 1.92 9.59 3.63 7.80 2017-15224 A13 GT037 6/6/2017 2.11 9.99 4.08 8.22 2017-15225 A14 RF024 6/7/2017 1.89 7.84 3.38 7.79 2017-15226 A15 JMK011 6/7/2017 1.52 9.28 3.54 7.67 2017-15227 A16 RF017 6/7/2017 1.73 9.51 3.67 7.89 2017-15228 A17 RF016 6/7/2017 1.71 9.27 3.78 8.02 2017-15229 A19 GT027 6/8/2017 1.64 9.44 3.77 7.74 2017-15230 A20 BLD012 6/8/2017 1.81 9.29 3.33 7.79 2017-15231 A21 BLD009 6/8/2017 1.65 9.35 3.59 7.58 2017-15232 A22 GT016 6/10/2017 1.67 9.15 3.36 7.75 2017-15233 A24 GT013 6/10/2017 1.73 9.65 3.41 8.26 2017-15234 A25 GT014 6/10/2017 1.69 9.17 3.35 7.86 2017-15235 A26 GT012 6/11/2017 1.73 9.49 3.50 8.36 2017-15236 A27 BLD008 6/11/2017 1.74 9.52 3.76 8.36 2017-15237 A28 BLD015 6/12/2017 1.67 9.49 3.66 7.59 2017-15238 A29 BLD018 6/12/2017 1.80 9.34 3.68 7.63 2017-15211 A30 BLD042 6/6/2017 1.59 9.63 3.69 7.60 2017-15212 A31 RF008 6/6/2017 1.82 9.21 3.55 7.96 2017-15213 A32 BLD037 6/6/2017 1.60 9.48 3.82 7.44 2017-15215 A34 GT020 6/7/2017 1.27 9.11 3.40 7.64 2017-15216 A35 GT018 6/7/2017 1.68 9.51 4.00 9.65 2017-15217 A36 BLD003 6/7/2017 1.63 9.27 3.82 7.77 2017-15218 A37 RF019 6/8/2017 1.88 10.15 4.01 8.02 2017-15219 A38 RF018 6/8/2017 1.75 9.48 4.13 9.40 2017-15220 A39 BLD028 6/8/2017 1.53 9.17 3.55 7.63 2017-15241 A40 RF004 6/8/2017 1.79 9.34 3.98 7.84 2017-15242 A41 GT046 6/8/2017 1.58 8.85 3.69 7.76 2017-15243 A42 GT045 6/8/2016 1.64 9.33 3.51 7.90 2017-15244 A43 GT041 6/8/2017 1.69 9.18 3.59 7.75 2017-15245 A44 BLD047 6/8/2017 1.80 9.37 4.10 8.02

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 20 Head Culmen Tarsus Band Tarsal Nest # Catch date Mass (KG) length length length number Code (cm) (cm) (cm) 2017-15247 A46 RF043 6/10/2017 1.72 9.49 3.41 7.86 2017-15248 A47 BLD001 6/10/2017 1.61 9.26 3.62 7.72 2017-15249 A48 BLD040 6/10/2017 1.46 9.16 3.65 7.40 2017-15250 A49 RF033 6/10/2017 1.74 9.71 3.86 7.87 2017-15261 A50 RF032 6/10/2017 1.69 9.50 3.75 8.04 2017-15262 A51 RF030 6/10/2017 1.65 9.44 3.80 7.53 2017-15263 A52 RF010 6/11/2017 1.74 9.83 3.77 7.65 2017-15264 A53 BLD038 6/11/2017 1.63 9.31 3.38 7.75 2017-15265 A54 GT008 6/11/2017 1.87 9.81 3.56 7.79 2017-15266 A55 GT006 6/11/2017 8.07 2017-15267 A56 BLD034 6/12/2017 1.61 8.95 3.67 7.69 2017-15268 A58 BLD021 6/12/2017 1.64 8.85 3.63 7.45 2017-15269 A59 BLD022 6/12/2017 1.97 9.32 3.96 8.00 2017-15239 A60 RF022 6/12/2017 1.62 9.62 3.49 7.56 2017-15240 A63 GT001 6/12/2017 1.54 9.00 3.41 9.85 2017-15251 A64 RF029 6/13/2017 1.45 8.92 3.81 7.14 2017-15252 A67 RF028 6/13/2017 1.64 9.16 3.32 7.75 2017-15253 A68 GT033 6/13/2017 1.57 9.65 4.06 7.70 2017-15254 A69 GT032 6/13/2017 1.59 9.25 3.55 7.95 2017-15270 A70 BLD025 6/12/2017 1.97 9.42 3.60 7.88 2017-15271 A71 BLD030 6/12/2017 1.80 9.32 3.84 7.99 2017-15272 A72 GT003 6/12/2017 1.65 9.23 3.75 7.90 2017-15273 A73 JMK004 6/13/2017 1.82 9.31 3.44 8.05 2017-15274 A74 JMK010 6/13/2017 1.57 9.23 3.78 7.63 2017-15275 A75 GT044 6/13/2017 1.61 9.11 3.79 7.27 2017-15276 A76 RF005 6/13/2017 1.61 9.25 3.71 7.82 2017-15277 A79 GT002 6/13/2017 1.86 9.67 3.93 7.98 2017-15255 A80 GT031 6/13/2017 1.75 9.48 3.72 8.00 2017-15256 A81 GT022 6/14/2017 1.89 9.44 3.48 7.73 2017-15257 A82 RF047 6/14/2017 1.83 9.74 3.63 7.77 2017-15258 A83 GT028 6/14/2017 1.62 9.12 3.40 7.79 2017-15259 A84 RF048 6/14/2017 1.41 9.22 3.74 7.84 2017-15260 A86 GT034 6/15/2017 1.81 8.90 3.20 7.67 2017-15291 A87 BLD007 6/15/2017 1.79 9.31 3.70 7.58 2017-15292 A88 GT042 6/16/2017 1.64 9.56 3.63 7.87 2017-15293 A89 RF027 6/17/2017 1.52 9.38 3.92 7.98 2017-15278 A90 RF045 6/14/2017 1.76 9.38 3.54 7.68 2017-15279 A92 GT015 6/14/2017 1.69 9.25 3.72 8.07 2017-15280 A93 BLD016 6/14/2017 1.73 9.56 3.49 8.16 2017-15281 A94 JMK002 6/14/2017 1.80 9.66 3.75 8.24 2017-15282 A95 BLD048 6/15/2017 1.73 9.52 3.88 7.56

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 21 Head Culmen Tarsus Band Tarsal Nest # Catch date Mass (KG) length length length number Code (cm) (cm) (cm) 2017-15284 A97 JMK007 6/17/2017 1.50 8.80 3.45 7.34 2017-15285 A98 GT040 6/19/2017 1.88 9.46 3.92 7.79 2017-15294 C00 RF039 6/17/2017 1.86 9.44 3.21 7.64 2017-15286 C01 MJA031 6/6/2018 1.65 9.56 3.85 7.64 2017-15287 C02 MJA019 6/6/2018 1.64 9.26 3.51 8.30 2017-15288 C03 MJA027 6/6/2018 1.68 9.05 3.64 7.84 2017-15289 C04 MJA029 6/6/2018 1.82 9.72 3.54 7.60 2017-15290 C05 BLD119 6/6/2018 1.64 9.25 3.62 7.06 2017-15295 C06 HMJ056 6/6/2018 1.68 9.36 3.61 7.75 2017-15296 C07 CPB063 6/6/2018 1.62 9.36 3.66 8.17 2017-15297 C08 MJA032 6/6/2018 9.05 3.41 8.12 2017-15298 C09 MJA016 6/7/2018 1.63 9.09 3.42 7.41 2017-15301 C10 MJA018 6/1/2018 9.50 3.55 7.64 2017-15302 C12 MJA003 6/1/2018 9.80 3.89 7.85 2017-15303 C13 JMT005 6/5/2018 1.66 9.03 3.48 7.97 2017-15304 C14 BLD112 6/6/2018 9.89 3.46 7.75 2017-15305 C15 BLD104 6/6/2018 1.82 9.25 3.62 7.45 2017-15306 C16 HMJ015 6/6/2018 9.28 3.67 7.45 2017-15307 C17 CPB037 6/6/2018 1.79 9.20 3.44 7.45 2017-15308 C18 HMJ022 6/6/2018 9.50 3.24 8.35 2017-15309 C19 MJA002 6/7/2018 9.25 3.66 7.46 2017-15311 C20 JMT117 6/8/2018 1.74 9.06 3.54 7.76 2017-15312 C21 JMT118 6/8/2018 1.60 9.16 3.59 7.84 2017-15310 C22 CPB002 6/7/2018 1.82 9.54 3.66 8.13 2017-15313 C23 JMT108 6/8/2018 1.88 9.65 3.74 7.98 2017-15314 C24 MJA203 6/9/2018 9.41 3.69 7.51 2017-15316 C25 JMT001 6/9/2018 1.65 9.12 3.53 7.24 2017-15315 C26 CPB072 6/9/2018 1.55 9.57 3.66 7.74 2017-15317 C27 HMJ024 6/9/2018 1.56 9.16 3.60 7.55 2017-15318 C28 MJA020 6/10/2018 1.76 9.56 3.80 7.85 2017-15343 C29 BLD118 6/10/2018 1.66 9.26 3.59 7.73 2017-15299 C30 MJA014 6/7/2018 9.51 3.78 8.06 2017-15300 C31 MJA009 6/8/2018 1.69 9.30 3.38 7.81 2017-15321 C32 BLD107 6/8/2018 1.76 9.56 3.74 7.86 2017-15322 C33 CPB023 6/8/2018 1.48 9.74 3.61 7.24 2017-15323 C34 CPB075 6/8/2018 1.63 9.64 3.79 7.93 2017-15324 C35 BLD111 6/9/2018 1.70 9.26 3.53 7.62 2017-15325 C36 BLD109 6/9/2018 1.54 9.29 3.93 7.82 2017-15326 C37 BLD108 6/9/2018 1.64 9.29 3.54 7.57 2017-15327 C38 MJA011 6/9/2018 1.82 9.09 3.54 7.91 2017-15328 C39 CPB036 6/9/2018 1.72 9.44 3.69 8.25

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 22 Head Culmen Tarsus Band Tarsal Nest # Catch date Mass (KG) length length length number Code (cm) (cm) (cm) 2017-15319 C41 CPB026 6/11/2018 1.58 9.12 3.43 7.25 2017-15320 C42 CPB024 6/11/2018 1.44 9.19 3.75 7.54 2017-15341 C43 JMT012 6/11/2018 1.69 9.37 3.72 7.62 2017-15344 C44 MJA035 6/12/2018 1.77 9.54 3.62 7.87 2017-15345 C45 JMT105 6/13/2018 1.56 9.44 3.54 7.98 2017-15346 C46 CPB069 6/13/2018 1.94 9.68 3.88 7.91 2017-15347 C47 MJA038 6/13/2018 1.52 9.29 3.36 7.51 2017-15348 C48 CPB080 6/13/2018 1.68 9.56 3.80 7.53 2017-15349 C49 JMT107 6/13/2018 1.57 9.44 3.93 7.77 2017-15329 C50 BLD114 6/9/2018 1.77 8.97 3.54 8.15 2017-15330 C51 MJA055 6/10/2018 1.57 9.39 3.92 7.02 2017-15331 C52 BLD106 6/10/2018 1.56 9.30 3.42 8.00 2017-15332 C53 HMJ060 6/10/2018 1.75 9.00 3.49 7.94 2017-15333 C54 JMT019 6/11/2018 1.45 9.05 3.52 7.62 2017-15334 C55 BLD115 6/11/2018 1.61 9.65 3.48 7.41 2017-15335 C56 JMT018 6/11/2018 9.18 3.58 7.40 2017-15336 C57 CPB008 6/12/2018 1.70 9.74 3.61 7.57 2017-15337 C58 CPB004 6/12/2018 9.04 3.45 7.73 2017-15338 C59 CPB003 6/12/2018 1.71 9.06 3.55 7.92 2017-15339 C60 MJA024 6/13/2018 1.73 9.62 3.80 7.92 2017-15340 C61 CPB048 6/13/2018 7.81 2017-15351 C62 MJA034 6/14/2018 1.75 9.74 3.89 7.82 2017-15352 C63 HMJ034 6/14/2018 1.76 9.46 3.85 7.75 2017-15353 C64 MJA037 6/14/2018 1.50 9.33 3.68 8.05 2017-15354 C65 CPB082 6/15/2018 1.68 9.83 3.66 7.90 2017-15355 C66 CPB065 6/15/2018 1.62 9.40 3.42 7.90 2017-15356 C67 HMJ061 6/19/2018 9.07 3.58 8.06 2017-15350 C70 CPB073 6/14/2018 9.16 3.16 7.40 2017-15361 C71 BLD113 6/14/2018 1.56 9.46 3.57 7.96 2017-15362 C72 CPB052 6/14/2018 1.53 9.15 3.34 7.66 2017-15363 C73 JMT131 6/14/2018 1.84 9.33 3.71 8.15 2017-15364 C74 MJA056 6/15/2018 1.57 9.24 3.70 7.22

USFWS, Yukon Delta NWR – Kigigak Emperor Goose Report, 2017 23