J-1503050-17 Wildlife Hazard Assessment and Management Plan (WHAMP).pdf

Wildlife Hazard Assessment and Management Plan NSA Souda Bay, Greece

October 2022

Prepared by: Paul Block

CNIC/NAVFAC BASH Program Natural Resource Lead

Table of Contents

1. INTRODUCTION

2. STRIKE HISTORY

3. METHODOLOGY

4. SURVEY RESULTS

5. HAZARDOUS SPECIES

5.1. Yellow‐legged Gulls

5.2. EURASIAN KESTRELS

5.3. Pigeons

5.4. Hooded Crows

5.5. Raptors

6. MANAGEMENT RECOMMENDATIONS

6.1. WASTE MANAGEMENT FACILITY MITIGATION

6.1.1. OPERATIONAL MANAGEMENT

6.1.2. GULL MITIGATION TECHNIQUES

6.1.3. COMMUNICATION PROCESSES

6.2. Habitat Management

6.2.1. TOPOGRAPHY

6.2.2. Vegetation Removal

6.2.3. MOWING REPETITION AND ACCURACY

6.3. Perch Removal

6.4. PERCH DETERRENTS

6.5. Dispersal Personnel and Harassment

6.6. OTHER TECHNOLOGIES

7. Other NSA Souda Bay Recommendations

8. Administrative Mitigation

8.1. Regular Meetings of BASH Working Group

8.2. Strike Submittals

8.3. Operational Mitigation

8.3.1. Flight Planning Considerations

9. Report Summary

10. Note

11. CONTACTS

12. References

13. Appendix A: Species Summary by Time of Day

14. Appendix B: Species Abundance by Survey Location

15. Appendix C: Seasonal Species Abundance

1. INTRODUCTION

Bird and wildlife aircraft strikes are a constant threat to the military mission through the degradation of flight operations that negatively affect training and military preparedness. Bird and wildlife aircraft strikes pose a safety hazard to pilots and aircrews and deplete military funds through aircraft loss and maintenance expenses. Given the proper tools and support, a Bird/Animal

Aircraft Strike Hazard (BASH) Program can effectively reduce bird and wildlife strikes on an airfield.

This report is a summary of observations and recommendations from four‐site visits to Naval

Support Activity Souda Bay (NSA Souda Bay) located in Greece to support the BASH Program at the installation. These surveys occurred seasonally in

June 2021 (8‐11), September 2021 (14‐17), February 2022 (15‐19), and April 2022 (5‐8). The surveys were conducted at Chania International Airport by Paul A. Block, CNIC/NAVFAC BASH Natural Resources

Program Lead with the assistance of NSA Souda Bay personnel. In this report, all references to NSA

Souda Bay include the Chania International Airport unless otherwise noted.

2. STRIKE HISTORY

NSA Souda Bay has 41 strike reports submitted (USA and USAF data) as of September 2022 in RMI and

AFSAS data systems. Of these submittals, 14 are identified to species or species group with 27 as unknown species or species group.

Strike identification to species was 34 percent of the total strikes. Table 1 summarizes strikes with identified species or species group. Species‐specific identification of remains is critical to any BASH program and assists with developing management techniques to mitigate aircraft‐bird interactions. Our goal is always 100% identification of strike remains by submittal to Smithsonian Feather ID Lab (SFIL).

Birds account for 100 percent of the identified species. Figure 1 shows the historical strikes by month

(USN and USAF data) of occurrence with the most strikes occurring in the months of May (6), August (5), and October (5). These three months accounted for 39% of all recorded strikes at NSA Souda Bay. These months are in spring and fall migratory periods, which includes typical resident movements around the airfield and increased migratory bird movements. These migratory movements include an increase in night movement of most migrating birds and an increase of high altitude raptor movements that occur during the day.

Thirty‐seven (37) of the recorded strikes (41) recorded time of day, 22% (8) of the strikes occurred within 1.5 hours of sunrise (after) and sunset (before). These two periods typically has the highest level

Flock of gulls crossing airfield of local bird movement as birds are dispersing to and from their daily feeding habitats from overnight roost locations so it is expected to see an increase in strikes during these periods and the limited data set does show this correlation. Nighttime flights account for 14% (5) of all recorded strikes. Four of the five occurred during spring and fall migratory periods with three occurring in the fall.

Additional strike data was provided by the Hellenic Air Force (HAF). This data set was incomplete as to date, and time. In addition, a small amount of commercial data was also received. This data was also partial only including 2018 data and lacking in specifics as to time, and date. The HAF reported 60 strikes from 2006 to 2020. Of these strikes, 54 were attributed to gulls with the other six unidentified. In the last three years, HAF has reported two mishaps, both involved gulls. In 2018, the commercial airport reported three mishaps and all involved gulls.

TABLE 1: LIST OF IDENTIFIED STRIKES BY SPECIES OR SPECIES GROUP (COMBINED USN, USAF, HAF, AND COMMERCIAL

DATA)

Species Number of Strikes Percentage of Total (101)*

Gulls: Yellow‐legged Gull; Black‐headed Gull; shorebird, gull, tern, etc. species

60 57

Tree Passerine: Willow Warbler; perching bird 2 2

Larks: Eurasian Skylark 3 3

Swifts: Common Swift, Alpine Swift 2 2

Ground Passerine: Eurasian Linnet 1 1

Falcons and Kestrels: Red‐footed Falcon; falcon sp. 2 2

Rock Pigeon 1 1

Unknown Species 33 33

Totals 101 100

*Rounded

FIGURE 1: THE NUMBER OF STRIKES BY MONTH FOR COMBINED USN AND USAF DATA‐ (HAF AND COMMERCIAL DATE

OF STRIKE DATA WAS UNAVAILABLE)

According to RMI and AFSAS data, NSA Souda Bay has had one Class B, two Class C, and two Class E

Mishaps because of bird strikes. These incidents are listed below.

Class B: 29 March 2018, an USN P‐8A struck an unknown species of bird on take‐off at approximately 13:20. Damage occurred to the outer‐edge of #1 engine cowling.

Class C: 26 May 2015, an USAF C‐35 struck a Red‐footed Falcon (Falco vespertinis), on its take‐off run at approximately 8:07. Damage occurred to two fan blades in #2 engine.

Class C: 17 August 2017, an USAF KC‐10 struck a flock of Rock Pigeons (Columba livia) during take‐off. Engine #1 suffered minor damage.

Class E: 14 March 2002, USAF C‐30 struck a Sora (Porzana carolina) causing minor damage. It is likely this strike occurred at a CONUS locations due to the species involved is endemic to North, Central, and South America and is not found in Greece. More details were not available.

Class E: 17 June 2007, USAF C‐135 struck an unknown bird denting a flap. More details were not available.

There is one BASH Program related report previously issued for NSA Souda Bay. This report is:

December 2014, U.S. Navy: Wildlife Hazard Assessment (WHA) for Naval Support Activity

Souda Bay, Crete. January –October 2014. Final Report.

This report made a number of recommendations. These recommendations are strong BASH Program management techniques and processes that may be implemented when and if practicable. These recommendations will result in an improved BASH environment and either directly or indirectly results in a decreased probability of a bird/wildlife strike.

3. METHODOLOGY

Five survey points were selected to separate the active runway, taxiways, and the adjacent areas into five approximately equal areas for the surveys (Figure 2). Surveys were conducted at each survey point three times a day. These survey periods included post sunrise, midday, and pre‐sunset. The starting survey point was staggered daily to remove time of day bias. For example, survey site on the first survey day started at Site A, the second day started at B, the third day at Site D, and the fourth day at Site E.

Four days of surveys were conducted during each of the four site visits or 192 total surveys (12 a day, 48 per visit). Each survey period lasted ten minutes. This equals 1,920 minutes of surveys or 32 hours for the entire year of surveys. All birds and wildlife observed were documented to species (Table 2) or species group. Binoculars and a camera were used to aide in identification and documenting habitat conditions.

FIGURE 2 ‐ SURVEY LOCATIONS AT NSA SOUDA BAY

4. SURVEY RESULTS

Each survey point is an index of the bird and wildlife usage at the location during that 10‐minute window of time. All of these surveys (winter, spring, summer, and fall) combined provide an overview of the seasonal, spatial, and temporal usage patterns of the airfield. Table 2 is a list of all bird species observed during the four survey periods. Many birds were identified to group rather than to species due to distance and/or low light that made species‐specific identification difficult or impossible. In addition, the purpose of a BASH survey species‐specific identification is not as important as observing and documenting as many bird groups during the survey period as possible. Therefore, categorizing birds into specific groups such as passerines, larks, wagtails, swallows, kestrels, and others is valuable since most species in these groups’ present similar BASH risks and have similar biological requirements. Table 2 also indicates the seasonal use of the airfield by particular species.

Common Buzzard and Eurasian Kestrel over airfield vegetation

TABLE 2: SPECIES OBSERVED BY SURVEYS ON THE AIRFIELD

Common Name Scientific Name June 2021 September

February

April

Alpine Swift Apus melba X

Barn Swallow Hirundo rustica X X

Black Redstart Phoenicurus ochruros X

Common Buzzard Buteo buteo X X X X

Common Chaffinch Fringilla coelebs X

Common House‐Martin Delichon urbicum X

Common Raven Corvus corax X

Common Swift Apus apus X

Crested Lark Galerida cristata X X X X

Eurasian Blackbird Turdus merula X X X

Eurasian Collared Dove Streptopelia decaocto X X X X

Eurasian Kestrel Falco tinnunculus X X X X

Eurasian Linnet Linaria cannabina X

European Greenfinch Carduelis carduelis X

European Hare Lepus europaeus X

European Stonechat Saxicola rubicola X X X

Hooded Crow Corvus cornix X X X X

Italian Sparrow Passer italiae X X X X

Lesser Gray Shrike Lanius minor X

Montagu's Harrier Circus pygargus X

Northern Wheatear Oenanthe oenanthe X X

Rock Pigeon Columba livia X X X X

Sardinian Warbler Sylvia melanocephala X X X

Tawny Pipit Anthus campestris X

Western Yellow Wagtail Montacilla flava X

Winchat Saxicola rubetra X X

Woodchat Shrike Lanius senator X

Yellow‐legged Gull Larus michahellis X X X

Appendix A summarizes the species observed by survey period (sunrise, mid‐day, and sunset). These tables show time of day abundance and movement patterns. Abundance of bird activity peaks the hour after sunrise and the hour before sunset each day. 2,048 birds were observed during all surveys, with

83% (1,694) observed during the sunrise and sunset survey periods. The sunrise period (957 observed) was approximately three times more birds observed than the mid‐day surveys (354 observed). Sunset surveys (737 observed) was approximately two times more birds observed than the mid‐day surveys.

The majority of the species observed belong to five groups or species: gulls, crows, larks, sparrows, and passerines.

Appendix B summarizes species abundance by survey location. These tables show species abundance associated with each survey location (Figure 2). Using combined data from all surveys, few species showed affinity for any survey point location with the exception of certain small bodied tree perching passerine species that tended to be located on the west two survey points using the small trees and large shrubs. Other groups and species that were only observed once or few couple of time may indicate location affinity but these are discounted due to lack of sufficient data.

Seasonal abundance is found in Appendix C. The most significant data showed gull abundance high in spring 2022 (April), summer 2021 (June), and winter 2022 (February) with summer abundance on the airfield the highest. In addition, the data shows that gulls were absent in the fall 2021 (September) survey with no gulls observed on the airfield or at the Waste Management Facility of Hania (WMFH).

This is discussed in detail in Chapter 5.1.

Other noticeable seasonal data is increased population of buzzards in the winter and fall. This shows that NSA Souda is on the migratory pathway for buzzards and an overwintering location for a small number of buzzards. Kestrel/falcon and larks numbers decrease in the winter and peak in the fall. Pigeon numbers increase in the summer. Finally, data shows that large groups of small‐bodied migrants

(passerines and wagtails) move through NSA Souda in higher numbers in the spring than in the fall.

5. HAZARDOUS SPECIES

Birds and wildlife are a threat to a safe flying environment at every airfield worldwide. An effective assessment of an airfields specific BASH hazards focuses on identification of species that are considered the most hazardous species at that airfield. The goal of the NSA Souda Bay WHA was to identify the most hazardous species and the conditions that attract these species with management recommendations to mitigate these hazards. These recommendations, if implemented, will decrease the probability of a bird and wildlife strikes and increase the safety of the flight environment protecting aircrews, aircraft, and the mission at NSA Souda Bay.

Table 3 shows the list of the most hazardous species identified at NSA Souda Bay. This list was developed using historical strike data (USN, USAF, HAF, and commercial data), WHA surveys, and body mass. This data is used to calculate a species relative hazard scores (RHS) (Pfieffer et al 2018) and a species abundance percentage. Body mass for each species or a species group body mass average was used to calculate RHS for each species or group. This RHS is a hazard indicator of species at NSA Souda

Bay but does not indicate current abundance conditions at the airfield. The Abundance Percentage is the percentage of each species or species group of the total number of observed birds during the WHA. The product of the Hazard Indicator and the Abundance Percentage gives the Weighted Strike Hazard for each species or species group at NSA Souda Bay. This number assumes that the historic strike data is accurate, current bird species located at the installation has not changed; and finally, is inclusive of all potential species that may be present seasonally at the airfield but potentially omitted due to not appearing in historic strike data. The Weighted Strike Hazard ranking is used for the following recommendations for the top hazardous species. Finally, to avoid zeroing out species observed on the airfield but never recorded in a strike, 0.01 was inserted to avoid an error calculation and to give these species a final score above zero. This arbitrary use of a number (0.01) is designed to overcome an incomplete strike record. Table 3 final two columns lists the Hazardous Species with and without including strikes since the strike total inclusion is problematic with some many unidentified species.

One addition point about this hazardous species list. The list uses identified strike species only and excludes all unidentified species. These unidentified species, if identified could significantly change the analysis of the data and therefore, significantly change the management recommendations. This point highlights that identification of all strikes by submitting samples to the SFIL is a vital part of the BASH

Program and should be adhered to by all flight commands at NSA Souda Bay.

Table 3: Hazard Ranking for Species at NSA Souda Bay

Species or Groups of Like Species

Historic al Strike Totals*

Relative Hazard or Averaged Hazard Scores incorporating Body Weight Estimates

Hazard Indicator (Hazard Score x Estimate d Strike Total)

Numbers Observed

(WHA

surveys)

Abundance Percentage

(Total Species Observations/

Total Observations)

Weighted Strike Hazard including number strikes

Weighted Strike Hazard omitting number of strikes

Yellow‐legged Gull, Gull sp.

60 37.42 2132.94 553 0.331933 707.99269 1.242092

Tree Passerine sp., Italian Sparrow, Sparrow sp.;

European Greenfinch;

Sardinian Warbler, Warbler sp.; Eurasian Stonechat; Common

Chiffchaff; Black Redstart;

Winchat

2 5.88 11.76 338 0.202881 2.385882 0.119294

Crested Lark, Lark sp. 3 7.01 21.03 180 0.108043 2.272149 0.075738

Eurasian Kestrel, Kestrel sp., Falcon

2 17.66 35.32 53 0.031813 1.123625 0.056181

Rock Pigeon 1 20.71 20.71 83 0.04982 1.031771 0.103177

Hooded crow, Crow sp. 0.1 27.25 2.725 325 0.195078 0.531588 0.531588

Ground Passerine sp.;

Northern Wheatear;

Wagtail sp.; Tawny Pipit;

Eurasian Linnet; Western

Yellow Wagtail

1 5.89 5.89 69 0.041417 0.243944 0.024394

Common Buzzard, Raptor sp.; Montagu's Harrier;

Harrier sp.

0.1 27.96 2.796 22 0.013205 0.036922 0.036922

Alpine Swift; Common Swift

2 9.15 18.3 3 0.001801 0.032953 0.001648

European Hare 0.1 63.88 6.388 2 0.0012 0.007669 0.007669

Barn Swallow; Common House‐Martin; Swallow sp.; Martin sp.

0.1 5.83 0.583 21 0.012605 0.007349 0.007349

Eurasian Collared Dove, Dove sp.

0.1 13.5 1.35 7 0.004202 0.005672 0.005672

Common Raven 0.1 39.68 3.968 2 0.0012 0.004764 0.004764

Woodchat Shrike; Lesser Gray Shrike; Shrike sp.

0.1 7.35 0.735 5 0.003001 0.002206 0.002206

Eurasian Blackbird 0.1 11.26 1.126 3 0.001801 0.002028 0.002028

*0.1 was used whenever zero was the actual number of strikes to avoid an error in calculation. This was done because of the large number of unknowns in the strike record.

Using Table 3 above, the following list details a few of the most hazardous species. The list skips the following three groups: tree passerines, larks, and ground passerines as these are small‐bodied groups that are difficult to manage against and unlikely to cause a mishap due to their low body weight. Larks are a year‐round resident and would be present regardless of efforts to mitigate. In addition, the abundance of tree and ground passerines are skewed by a few large group observations during migratory movements.

In each species narrative, some mitigation is recommended. These recommendations are discussed in detail in Chapter 6.

5.1. Yellow‐legged Gulls

Gulls are the most hazardous species at NSA Souda Bay and the greatest threat to flight safety. The hazard score for gulls (incorporating strikes) is

297‐times the next closest hazard score. They have been in at least 60 reported strikes (USA, USAF, HAF, and commercial data). The most common species of gulls at NSA Souda Bay is the

Yellow‐legged Gull (Larus michahellis). During post sunrise surveys (spring, summer, and winter), individual and flocks of gulls (226 gulls total observed) flying from the west cross the airfield and airspace of NSA Souda Bay heading directly to the WMFH located northeast of the airfield. During mid‐day surveys (spring, summer, and winter), gulls (71 gulls total observed) would fly through the airspace going both directions but at lower numbers than the other surveys periods. In addition, during pre‐sunset surveys (spring, summer, and winter), individual and flocks of gulls (254 total observed) are flying from the northeast across the airfield and airspace to locations west of the installation. These observations occurred at every survey point.

Yellow‐legged Gull

Survey data shows gull abundance high in spring 2022 (April), summer 2021 (June), and winter 2022

(February) with summer abundance on the airfield the highest. In addition, the data shows that gulls were absent in the fall 2021

(September) survey with no gulls observed on the airfield or at the

WMFH. It appears that the gulls observed in winter 2022 and summer 2021 are from two separate populations. The gulls observed in summer 2021 are a breeding population that is likely present from March/April to

July/August. This population appears to disperse or migrate from the area and NSA Souda Bay from

July/August. The gulls observed in winter 2022 are a winter resident population that likely arrives from northern locations in the late fall or early winter (late October/November) and remain through late winter to early spring (late

February to March). Therefore, if this is what is occurring with the gull population, then the period of September/November and

February/March should show a decrease in gull activity at NSA Souda Bay as these populations migrate. Data shows the decrease in gulls in

September but a matching decrease in

February/March would require a March survey to confirm.

Off installation investigations found large numbers of gulls (spring, summer, and winter) located at the WMFH located 1.9 miles northeast of the eastern approach of the airfield. The three photos on the following page illustrate the numbers located during one observation in April

2022. This facility is the attractant for gulls to the area. This facility at times would have hundreds of gulls on the open refuse piles feeding. Additionally, on several occasions large flocks of gulls observed in a kettle (tornado‐like formation of circling birds) near the WMFH. These kettles span a wide AGL from top to bottom. On one occasion, a large kettle of gulls formed in the airspace of the east approach (see photo on page 27) that threatened approaching flights. On two other occasion, smaller kettles of gulls formed over the airfield, once over B ladder and once over D ladder that required a pause in operations on the airfield. The larger

Large aerial formation (kettle) of gulls just northeast of airfield. Every black dot is a gull and photo is only a part of the total formation

Gulls resting on Navy ramp kettle formations observed (see one example in photo on page 12) included over a thousand gulls. It is important to note, that these formation are vulnerable to drift and are not spatially static so if they form near the landfill they may and do drift into NSA Souda Bay airspace.

Recommendations for Gulls

Decreasing the probability of a BASH incident involving gulls is a challenging issue and are discussed in three categories: loafing, flying gulls, and WMFH mitigation. WMFH mitigation is discussed in Chapter

6.1. Tools and techniques mentioned in Chapter 5 are discussed in detail in Chapter 6.

Loafing Gulls

Loafing gulls are attracted to the airfield environment for several reasons including food, warmth, and freshwater. Airfield sweeps prior to any aircraft arrivals and departures to disperse any loafing birds is recommended. The sweeps should look for gulls but also potential food attractant such as animal carcasses.

The use of harassment tools such as pyrotechnics, vehicle mounted air cannon, laser during low light conditions should be considered to move gulls from the airfield environment. Other harassment techniques as simple as approaching with a vehicle may be effective in moving gulls off the airfield.

Flying Gulls

Flying gulls represent a greater challenge than loafing goals. Based on observations, gulls fly across the airfield and the airspace of NSA Souda Bay are in highest numbers during the post sunrise and pre‐ sunset as they make daily movements to and from the WMFH. Time of day restrictions for flight operations would be the most effective policy to decrease the probability of a gull strike for gulls crossing the airfield in flight. Limiting operations for one hour before and two hours after sunrise and two hours before and one hour after sunset would be the ideal restrictive period.

If this type of restriction is not possible due to mission requirements, then a mandatory Moderate Bird

Strike Threat alert should be set for these sunrise and sunset periods. Tower personnel should track activity levels of all birds but especially gulls and alerts should be included in all pilot advisories and

NOTAMS. If levels of activity appear high, then a HIGH Bird Strike Threat alert should be set until the threat is deemed over or downgraded.

5.2. EURASIAN KESTRELS

Eurasian Kestrels (Falco tinnunculus) are the one of the most hazardous species at NSA Souda Bay.

Historically, kestrels have been responsible for two of the identified strikes. Kestrels were observed during all WHA surveys (73) and are year‐round resident but were most abundant during the spring (14), summer (19), and fall (33) surveys. Kestrels were observed at all five survey points but were more common at point A (21) and Point B (23). Kestrels ere also observed throughout the day but were more often observed during mid‐day (30) and pre‐sunset (25) surveys.

The following are steps that can be taken to decrease the abundance of kestrels on the airfield. Many of these steps are discussed in detail in Chapter 6.

Habitat reduction:

o Removal of trees and shrubs in airfield environment.

This decreases hunting and roosting locations (discussed in Chapter 6).

o Mow airfield environment regularly to prevent tall vegetation from going to flower and seed. This decreases food availability to kestrel prey species (discussed in Chapter 6).

o Decrease topography on the airfield. This decreases prey availability to kestrels

(discussed in Chapter 6).

o Remove obsolete elevated manmade items such as signs, lights, poles, antennas, fences, and other items. This decreases hunting and roosting locations (discussed in Chapter 6).

o Add perch deterrents to all elevated manmade items such as signs, lights, poles, antennas, fences, and other items. This decreases hunting and roosting locations

(discussed in Chapter 6).

o Removal of all shrubs and trees in that border airfield environment (Chapter 6, Figure 3).

Awareness and harassment (discussed in Chapter 6):

o Conduct pre‐operational taxiway and runway sweeps.

o Harass kestrels as needed on the airfield‐by‐airfield personnel. Harassment tools may include lasers, spotlights, sound devices, and pyros.

Eurasian Kestrel perched on utility pole near eastern end of the north taxiway

5.3. Pigeons

Pigeons are one of the most hazardous species at NSA Souda Bay. This ranking is based on a medium body mass, prevalence in the strike database, and abundance during WHA surveys.

Rock and Feral Pigeons comprise this group. Historically, pigeons have been responsible for one of the identified strikes. Pigeons were observed during all WHA surveys (87) and are year‐round resident but were most abundant during the spring (20), and summer (56) surveys. Pigeons were observed at all five survey points but were more common at point

B (29), Point C (27) and Point

D (20). Pigeons were also observed throughout the day but were more often observed during post sunrise (45) and mid‐day (39) surveys. Pigeons though not particularly large birds are dense in weight, form flocks when not in the breeding season, and are increasing their populations around man‐influenced habitats. Pigeons use buildings and other manmade infrastructures for roosting and nesting and are commonly found in hanger buildings were they are considered nuisance and a potential health hazard.

Pigeons were observed in flight across the airfield and feeding in the vegetated areas. Pigeons in the vegetated habitats are foraging for seeds and collect grit for digestion. The following are steps that can be taken to decrease the abundance of pigeons on the airfield. Many of these steps are discussed in detail in Chapter 6.

Habitat reduction:

o Mow airfield environment regularly to prevent tall vegetation from going to flower and seed. This decreases food availability (discussed in Chapter 6).

o Remove obsolete elevated manmade items such as signs, lights, poles, antennas, fences, and other items. This decreases roosting locations (discussed in Chapter 6).

o Add perch deterrents to all elevated manmade items such as signs, lights, poles, antennas, fences, and other items. This decreases roosting locations (discussed in

Chapter 6).

o Ensure that landscape plantings do not produce bird attractants such as seeds, nuts, and fruits. This decreases food availability (discussed in Chapter 6).

Awareness and harassment (discussed in Chapter 6):

o Conduct pre‐operational taxiway and runway sweeps.

o Harass pigeons as needed on the airfield‐by‐airfield personnel. Harassment tools may include lasers, spotlights, sound devices, and pyros.

Rock and Feral Pigeons

Other:

o Use depredation around buildings and inside hangars at NSAS Souda Bay.

o Preventing hangar usage with netting or hanging door curtains/barriers, or closing hangar doors during the day (if outside temperatures allow).

5.4. Hooded Crows

Hooded Crows do not show up in the identified strike record for NSA Souda Bay but it is the second most abundant species observed during surveys. However, with the abundance of this species, daily movement across the airspace, and the medium body mass, this species ranks as one of most hazardous species at NSA Souda Bay. During WHA surveys, 479 crows were observed. Crows are year‐round residents but were observed more often during winter and fall surveys but were present on the airfield in every survey period. Crow abundance was greatest during dusk surveys with 238 (49.7%) observed during pre‐sunset surveys and second most abundant during post sunrise surveys with 195 observed (40.7%).

During surveys, crows were most commonly observed foraging in the vegetated areas as individuals, pairs, or small loose flocks during pre‐sunset (195) and post sunrise (238) surveys. Spatially, this group has a greater abundance in the middle of the airfield with the majority of observations at Points B (124), C (122), and D (100). Most of the year, crows are social, but during nesting season, crows form breeding pairs and become less social dispersing to use a wide variety of trees and other elevated areas for nesting. They feed on almost anything including carrion, birds (nestlings and eggs), small mammals, reptiles, insects, other invertebrates, seeds, fruits, and human trash.

Hooded Crows are highly intelligent animals and generally avoid aircraft but like all birds, are vulnerable to aircraft moving at high velocity. The following are steps that can be taken to decrease the abundance of crows on the airfield. Many of these steps are discussed in detail in Chapter 6.

Habitat reduction:

o Removal of trees and shrubs in airfield environment. This decreases hunting and roosting locations (discussed in Chapter 6).

o Mow airfield environment regularly to prevent tall vegetation from going to flower and seed. This decreases food availability to prey species and crows (discussed in Chapter 6).

o Decrease topography on the airfield. This decreases food availability (discussed in

Chapter 6).

o Remove obsolete elevated manmade items such as signs, lights, poles, antennas, fences, and other items. This decreases hunting and roosting locations (discussed in Chapter 6).

Hooded Crow on taxiway o Add perch deterrents to all elevated manmade items such as signs, lights, poles, antennas, fences, and other items. This decreases hunting and roosting locations

(discussed in Chapter 6).

o Removal of all large trees on base (taller than 20 feet). This decreases nesting locations.

o Ensure that landscape plantings do not produce bird attractants such as seeds, nuts, and fruits. This decreases food availability (discussed in Chapter 6).

o Future base contract should include that all trees are pruned to maintain an open canopy that will decrease the area available of nesting and roosting.

o Work with Airport and HAF on reducing the numbers of large trees on their properties and pruning those that remain to open the canopy. Reduces roosting and nesting locations.

o Removal of all shrubs and trees that border airfield environment (Chapter 6, Figure 3).

This decrease roost and nest locations.

Awareness and harassment (discussed in Chapter 6):

o Conduct pre‐operational taxiway and runway sweeps.

o Harass crows as needed on the airfield‐by‐airfield personnel. Harassment tools may include lasers, spotlights, sound devices, and pyros.

o Increase awareness during and after mowing occurs as mowing caused mortalities may attract crows and raptors.

o Remove any carcasses found on airfield surfaces and local roadways. These are attractants to crows and raptors.

Other:

o Secure all trash receptacles on base. Secure all trash being collected and transported while exposed in the back of vehicles.

o Work with local landfill to cover all food scrap and animal carcass disposals. Discussed in

Chapter 6.

5.5. Raptors

Common Buzzard (Buteo buteo), and Montagu’s Harrier (Circus pygargus) comprise the raptor group for observed birds at NSA Souda Bay. The species most often observed on the airfield was the Common

Buzzard with Montagu’s harrier observed on one occasion. Historically, raptors have not been confirmed as responsible for a strike at NSA Souda Bay, but this species requires consideration as one of the most hazardous species because of the large body size, soaring flight, use of open spaces, and prevalence (Common Buzzard and similar species) in the full strike database. Raptors were observed during all WHA surveys (38) and are year‐round resident but were most abundant during the winter

(15), and fall (16) surveys. Raptors were observed at all five survey points showing no preference for any spatial area of the airfield. In addition, raptors were observed throughout the day with no time of day preferences.

The following are steps that can be taken to decrease the abundance of raptors on the airfield. Many of these steps are discussed in detail in

Chapter 6.

Habitat reduction:

o Removal of trees and shrubs in airfield environment. This decreases hunting and roosting locations

(discussed in Chapter 6).

o Mow airfield environment regularly to prevent tall vegetation from going to flower and seed. This decreases food availability for prey species (discussed in Chapter 6).

o Decrease topography on the airfield. This decreases food availability (discussed in

Chapter 6).

o Remove obsolete elevated manmade items such as signs, lights, poles, antennas, fences, and other items. This decreases hunting and roosting locations (discussed in Chapter 6).

o Add perch deterrents to all elevated manmade items such as signs, lights, poles, antennas, fences, and other items. This decreases hunting and roosting locations

(discussed in Chapter 6).

o Removal of all large trees on base (taller than 20 feet). This decreases hunting, nesting, and roosting locations (discussed in Chapter 6).

o Ensure that landscape plantings do not produce bird attractants such as seeds, nuts, and fruits. This decreases food availability for prey species (discussed in Chapter 6).

o Future base contract should include that all trees are pruned to maintain an open canopy that will decrease the area available of nesting and roosting.

o Work with Airport and HAF on reducing the numbers of large trees on their properties and pruning those that remain to open the canopy. This will decrease roosting and nesting.

o Removal of all shrubs and trees that border airfield environment (Chapter 6, Figure 3).

This decreases roost and nest locations.

Awareness and harassment (discussed in Chapter 6):

o Conduct pre‐operational taxiway and runway sweeps.

o Harass raptors as needed on the airfield‐by‐airfield personnel. Harassment tools may include lasers, spotlights, sound devices, and pyros.

o Increase awareness during and after mowing occurs as mowing caused mortalities may attract crows and raptors.

o Remove any carcasses found on airfield surfaces and local roadways. These are attractants to crows and raptors.

Common Buzzard

6. MANAGEMENT RECOMMENDATIONS

These are management recommendations designed for short and long‐term solutions that significantly decrease BASH hazards at NSA Souda Bay. These recommendations include WMFH mitigation, habitat management, perch removal, installing perch deterrents, and dispersal and harassment.

6.1. WASTE MANAGEMENT FACILITY MITIGATION

Of all the mitigation recommendations, easily the most important is the mitigation of the WMFH. WMFH is located 1.9 miles northeast of the eastern approach of the airfield. WMFH is the attractant of gulls to the area and gulls are the most hazardous species to the airfield responsible for 60‐recorded strikes (USN, USAF, HAF, and commercial data). The relaxed manner of the waste management at WMFH is responsible for the attraction of gulls. This facility subsidizes gulls with food that would not ordinarily be available to gulls in the area. This human‐caused food source artificially increases the local gull populations to numbers that without the landfill would likely exceed the carrying capacity of the local habitats to this large population of gulls. Without the landfill’s artificial food source, gulls would not fly across the airspace daily and would likely be a rarely observed on the airfield or in the airspaces around the airfield.

Part of the population feeding at WMFH (spring and summer) breed locally on Palaiosouda located off the coast of Marathi southeast of the eastern approach of the airfield (see map). Observations during summer surveys indicated that this island likely support hundreds of breeding pairs of Yellow‐legged Gulls.

These gulls were observed flying back and forth from the island to WMFH following the coastline in daily flight to collect food for to feed gull chicks.

During observational visits to WMFH, gulls were observed during the winter, spring, and summer periods but no gulls were observed in the fall. During the periods in which gulls were present, at times, hundreds of gulls were observed on the active face (area of exposed trash) feeding on the exposed refuse (see Chapter 5.1 photos). These gulls while feeding on the active face are not a threat to flight safety at NSA Souda Bay. However, as described before, the gulls feeding on the active face fly through the airspace on ingress and egress flights each day. Many of these daily flights cross directly over NSA

Gull breeding island (green), WMFH

(red) and the ingress and egress pathway (yellow)

Souda Bay. Additionally, as observed on several occasions, large numbers of gulls (hundreds to thousands) would form large kettling flights (see Chapter 5.1) above WMFH that reached heights of several hundred AGL if not higher. These flocks are not spatially stagnate, drifting with the winds that at times places these large flocks in NSA Souda Bay’s airspace. During airfield surveys, on two occasions, gulls were observed forming smaller flocks (50 plus individuals) in low AGL kettles direct over the airfield.

It is recommended that in coordination and cooperation with the HAF and the Chania International

Airport that USN work with the local municipality that owns and operates WMFH to develop and implement a WMFH Gull Abundance Reduction Plan designed to make operational management improvements and implement gull mitigation at the landfill. The following are recommendations for better operational management to decrease food availability; gull mitigation techniques; and communication processes that implemented in concert and maintained will significantly decrease the population of gulls at WMFH.

6.1.1. OPERATIONAL MANAGEMENT

WMFH has operational deficiencies that are common in landfill management. Primarily the large area of an active face (exposed area of trash) is the attractant to gulls looking for an easy available artificial food source. The following are recommendations for operational improvements.

Implementation of all or some of the recommendations should decrease exposed food available to gulls and decrease the abundance of gulls at the WMFH.

Reduce the size of the active face by burying areas of exposed trash throughout the day.

At the end of each day, fully bury or cover active face with tarp.

Have a designated person or team that picks up stray trash outside of the active face to return to active face and to area covered by tarp.

Remove large area of standing freshwater. Freshwater is an additional attractant to gulls.

An additional idea that could be effective is to have all trash trucks bring in new trash during the night.

Example of tarp use to cover the active face

Example of tarp use to cover the active face

6.1.2. GULL MITIGATION TECHNIQUES

Operational changes alone will be valuable but to complete the reduction of gulls at WMFH, implementation of gull mitigation techniques designed to disperse gulls from the landfill is a vital part of the plan. It is important to understand that anyone gull mitigation technique alone has limited efficacy and that the best approach is to incorporate multiple techniques. The following are recommendations for mitigation techniques.

Station full time trained wildlife dispersal personnel/s during daytime hours at WMFH.

Use multiple techniques to harass gulls including the following:

o Pyros o Propane cannons o Lasers o Paintball guns o Slingshots o Whistles and other sound making equipment

Depredation of gulls

Using gull effigies as a deterrent. Tossing into the air or hanging in a visual place.

Falconry can be highly effective tool in this situation

Any other harassment technique used in tandem with the others.

Variety is the most important recommendation so gulls do not habitualized to anyone tool or technique through over use. Proper implementation of both operational and gull mitigation should drastically decrease the numbers of gulls at the landfill.

6.1.3. COMMUNICATION PROCESSES

The final step to decrease strike potential with gulls is to implement a direct communication process between WMFH and Chania International Airport ATC in order to warn the airfield of current gull hazards at WMFH. This is necessary, as large numbers of gulls in flight are difficult to observe from a distance in a bright sky. WMFH should assign appropriately trained personnel the duty of gull activity observations both of gulls on the landfill and in the airspace during daylight hours. Observational criteria should be developed that trigger communication with the ATC by WMFH personnel. These observational criteria may include a certain number of gulls on the landfill but most importantly should include observations kettling gulls that form in the airspace above and near the WMFH. The WMFH personnel should be provided binoculars to aide in counting of gulls and the observation of airborne flocks. These personnel should also have the appropriate contact numbers for the ATC. Once ATC is alerted, ATC personnel should follow developed procedures that set airfield hazard‐level as appropriate. ATC should notify Navy ATOC and Chania International Airport authority of status as appropriate.

6.2. Habitat Management

Vegetation and topography provide cover for birds and wildlife so habitat management is an important

BASH tool. The vegetation around the airfield is diverse with a variety of herbaceous and woody species. These plants are a food source (nuts, flowers, fruits, and seeds) for birds and other animals that birds and larger mammals prey on such as small mammals, reptiles, insects, and other invertebrates.

One strategy for NSA Souda Bay is to reduce seed, flowering, and fruiting plants to reduce the populations of insects, invertebrates, reptiles, and small mammals that attract birds and larger mammals. Additionally, the more varied and complex a habitat is the more species of wildlife it attracts. Decreasing this habitat complexity is a goal of habitat management. These habitat management recommendations are discussed below.

6.2.1. TOPOGRAPHY

Topographical variations give the airfield habitat for a variety of wildlife. Small hills, ditches, stone piles, and manmade debris are all types of topographic variation that should be removed.

Most of the topographical variation is from rock piles in various locations. These areas can be habitat for insects, invertebrates, reptiles, and small mammals that are food attractants for birds and larger mammals. Most of the vegetation issues on the airfield are located in and around areas of topographical issues because mowers cannot access.

It is recommended that a project be developed and implemented to provide the airfield with the following:

Level soil to decrease topographic variation

Removal of all airfield debris (natural and manmade) to allow mower access

Areas of unnecessary topography in airfield vegetated spaces and a variety of associated shrubs and small trees, all increase birds on airfield

Fruiting shrubs attract birds and insects

6.2.2. Vegetation Removal

Due to climate limitations, a dense cover of turf‐type grass is not practicable at NSA Souda Bay;

therefore, removal of all shrubs and trees within the airfield and adjacent habitats (yellow areas in

Figure 3) is one of the best strategy for decreasing bird and wildlife usage on the airfield. Therefore, all shrubs and trees should be removed from the airfield and its adjacent environments and these areas be maintained to limit regrowth. In Figure 3, one section delineated in red contains two large trees. One of these trees contained a large nest that was likely a raptor or crow nest when active. These two trees should be removed. All vegetation management areas are delineated in Figure 3.

Figure 3: Vegetation Clearance Areas

Trees at west end, one with large nest

A few of the trees and shrubs growing between taxiway and runway

Birds use trees and shrubs for habitat

6.2.3. MOWING REPETITION AND ACCURACY

Additional recommended habitat measures are to increase how often mowing occurs. It is apparent that in areas that are mowed, that the period between mowing is too long and this allows herbaceous vegetation to grow taller and go to flower, fruit, and seed. This taller vegetation gives shelter for birds, insects, reptiles, and small mammals. The fruits and seeds are food for various birds, insects, and small mammals. In addition, the flowers are an attractant to a variety of insects. All of these act as direct or indirect attractant to a variety of birds. For example, less insects would decrease Eurasian Kestrels (Falco tinnunculus), less seeds and insects would decrease

Crested Larks (Galerida cristata), and less small mammals would decrease Common Buzzards (Buteo buteo).

Mowing accuracy should include mowing all herbaceous vegetation as short as possible given the topographic conditions and to mow to the edge of the taxiways and runways to eliminate edge habitat.

The taller vegetation that is often next to the hard surfaces attracts a variety of species for the same reasons as described in the preceding paragraph. It addition, this draws these species right to the edges of where aircraft movements occur.

6.3. Perch Removal

NSA Souda Bay has many perch locations in the immediate airfield environment and adjacent areas.

These perches include trees and manmade items such as signs, lights, poles, antennas, fences, and other items. Many bird species use these perches but the primary hazard is from larger bodied species.

Buzzards, kestrels, and crows use perches as elevated hunting locations as well as for roosting. Elevated perches are especially important to these large‐bodied predatory species for locating prey/carrion before flying down to feed. In‐flight hunting for large‐ bodied raptors is not the preferred hunting strategy and without elevated perches, the area becomes

Eurasian Kestrel loafing on signage next to west end of runway on sign without perch deterrents

Edge Habitat should be removed

Vegetation at various heights and in flower less usable for hunting and other off airfield forage areas will be sought. Trees and large bushes are also hunting perches and the vegetation‐clearing project discussed above removes all vegetation related perches.

6.4. PERCH DETERRENTS

Any perches (signs, lights, poles, fences, antennas, windsocks, and other items) in the airfield environment or the adjacent areas that cannot be removed should have perch deterrents such as spikes installed on all horizontal surfaces. Adding anti‐perching devices to airfield signs, lights, and other tall manmade structures may help prevent or limit hunting and roosting by some species in the airfield environment especially large‐bodied birds such buzzards, kestrels, and crows. This may also help reduce owl usage of the airfield. Perch deterrents should be selected and installed properly with the total perch area covered with high density, height appropriate spikes (use four inches or longer) with angled spikes overlapping all edges of the perch. This may take more than one row of spikes to cover a broader area and not leave space between each row. Poles and other single small pinnacle perches should be covered with a sharp‐tipped cone to prevent perching but the cone must cover the entire surface and no leave edges. One possible manufacturer for pole caps is Zena Design at http://www.zenadesign.com. This is not a specific endorsement of particular manufacturer but rather an example of what design has a better chance of efficacy at NSA Souda Bay. Once installed, these deterrents should be monitored, maintained, repaired, and replaced as needed.

If all unnecessary perches are removed and all remaining perches have deterrents installed that effectively limit their usage as hunting or roosting locations, then most large‐bodied raptors, will move off the airfield environment and fewer smaller‐bodied raptors will use the open airfield environment.

This would effectively decrease the BASH hazard of the largest‐bodied birds that may use the airfield.

6.5. Dispersal Personnel and Harassment

Various techniques exist that can decrease BASH hazardous in the airfield environment. Currently, the

HAF has an active wildlife dispersal team that manages the HAF‐side of the airfield and the runway. This team conducts pre‐HAF aircraft operations sweeps of the runway by driving the runway dispersing any birds loafing on the runway. In addition, the HAF team operates several propane air cannon that are fired periodically and maintained daily. It is recommended that through coordination with the HAF that either permission is gained for the HAF wildlife dispersal team to add runway sweeps for pre‐US aircraft operations or get HAF permission for the Navy to stand up a Wildlife Dispersal Team (WDT) to conduct pre‐US aircraft operations sweeps of the runway.

The preferred option would be the Navy to establish a WDT. The WDT should be trained prior to implementation. In theater USDA Wildlife Services biologist would been the appropriate trainer if this can be coordinated with EURAFCENT. This Navy WDT should have four duties at NSA Souda Bay. These duties are active observation, runway sweeps, harassment, and communication.