Report on the Low Level Road Project Regarding Bald Eagle ... · Since the ban of DDT and DDE...

January 2013 – Low Level Road Project – Mitigation Measures – Bald Eagle Habitat

Ian Galsworthy Port Metro Vancouver 100 The Pointe, 999 Canada Place Vancouver, BC Canada V6C 3T4 direct: 604.665.9244 mobile: 604.753.9906 fax: 1.866.284.4271

January 30, 2013

Report on the Low Level Road Project Regarding Bald Eagle Nest Mitigation

As a long time advocate for bald eagles I was at first sad to learn that the 5 year efforts of a bald eagle pair to establish, while unsuccessfully, a nest on the Port Metro Vancouver property in North Vancouver was coming to an end. Then I learned that a permit to remove this nest had been given by the Ministry of Environment, but that there was a possible positive upside for eagles. MOE was demanding mitigation, and this mitigation was being very positively viewed by Port Metro Vancouver.

I have had to stand by over the years and idly watch eagle nests come down and no mitigation had been forthcoming. The fact that mitigation is happening I am now so pleased to be able to “stand in for the eagles” and offer suggestions as to what they need in return. This cooperative project between the MOE, PMV and private consultation is a positive landmark project. That the eagles will gain far more than they are losing is a tribute to the cooperative effort of the MOE and Port Metro Vancouver.

Thank you for giving me this opportunity to speak for the eagles. I look forward to completing the artificial nest installations.

Enclosed are my final proposals and recommendations on what can be done along the North Shore to positively mitigate the loss of the Esplanade bald eagle nest.

Regards,

David Hancock

Bald Eagle Biologist

Hancock Wildlife Foundation 19313 Zero Avenue, Surrey BC V3S 9R9 (604) 538-1114


Low Level Road Project – Mitigation Measures – Bald Eagle Habitat

Introduction The Low Level Road Project is part of a broader investment and improvement strategy on behalf of the Government of Canada, Province of British Columbia, Port Metro Vancouver, TransLink, the City and District of North Vancouver and the private sector. The strategy is designed to facilitate projected port-related growth to meet international trade demands while maximizing benefits and minimizing impacts on local communities. As a primary east-west route for the North Shore, the importance of the Low Level Road has long been reflected in community and transportation plans. Upgrades on this road are required to improve safety and better accommodate the needs of all users including cyclists and pedestrians. The project is important to Port Metro Vancouver because it provides for more efficient operations for tenants and provides community benefits for the City of North Vancouver. These benefits include minimizing noise impacts from Port operations, a permanent solution to unstable cut slopes above the existing road and completion of the Spirit Trail between St. Georges Avenue and Kennard Avenue. Key elements of the project include: • Re-alignment of the Low Level Road to the north • Providing space for two new rail tracks to improve rail efficiencies • Eliminating three existing at-grade rail crossings • Providing intersection and road safety improvements between the Esplanade/Low Level Road intersection, and the East 3rd Street/ Cotton Drive/Low Level Road intersection • Addressing slope stability along the Moodyville bluff • Addressing long-standing safety, recreation and noise challenges associated with Port operations along the existing Low Level Road • Completing the Spirit Trail and providing upgraded cycling and pedestrian facilities. Background on Eagles The eagle is one of nature’s most impressive birds of prey. Males generally measure 3 feet from head to tail, weigh 6 to 8 pounds, and have a wingspan of 5.5 to 6.5 feet. Females are larger, some reaching 14 pounds with a wingspan of up to 7 feet. Eagles are opportunistic predators. They feed primarily on fish, but also eat a variety of waterfowl and other birds, small mammals, and turtles, when these foods are readily available. Carrion is also common in the diet, particularly in younger birds. Small road killed mammals and feral pigeons, first killed by peregrines, are prime food source for nesting eagles. Bottom-dwelling fish tend to occur more frequently in the diet. Eagles capture fish by extending their talons a few inches below the water's surface. Therefore, live fish are vulnerable only when near the surface or in shallows. Eagles nest from October to July. Nests are constructed primarily by the female, with the male assisting. The typical nest is constructed of large sticks, with softer materials such as leaves, grass, and Spanish moss used as nest lining. Nests are typically used for a number of years, with the birds adding nest material every year. Eagles often have one or more alternative nests within their territories. Eagle nests


are generally found from 15 to 36 meters (50 to 120 feet) above the ground, in a tall, sturdy tree but in recent years nest regularly on man-made structures. It takes at least two weeks for a pair of eagles to build their nest. A typical bald eagle nest (eyrie) will range from 1.2 to 2.5 meters (4-8 feet) in diameter and about 0.8 to 2 meters (2 to 6 feet) high. The nest cavity, where the eggs are laid, will be about 30 to 40 centimeters (12 to 16 inches) in diameter and about 10 centimeters (4 inches) deep. Peak egg-laying occurs in March and April, with hatching primarily in April and May. The female lays a clutch of 1 to 3 eggs, but the usual clutch is 2 eggs. A second clutch may be laid if the first is lost early in incubation. Incubation begins when the first egg is laid and usually lasts 34 to 36 days. The young generally fledge (fly from the nest) in 12 weeks, but the adults continue to protect them for another 1 to 2 weeks while in the nest territory when the young are abandoned. When they are on their own, young eagles migrate, returning to the region in October or November after feasting on the spawned salmon to the north. It has been stated for many years that an eagle pair will mate for life, but if one partner dies, or disappears, the other will generally find another mate. A newly bonded pair may work several years on a nest before actually breeding but frequently nest successfully the first year. They may desert one nest site and start again somewhere else within the territory; this usually extends about 1 to 2 kilometers (1/2 to 1.25 mile) along the shoreline. In food rich flood plains or farmland crossed with ditches and lots of food , the eagles can nest less than 0.5 kilometer apart. An eagle will return to defend the nest territory in October and then put more effort into the nest rebuilding in January and February. Each nesting pair will spend a great amount of time preparing the nest before any egg is laid. The successful nest is generally located in a large tree very close to water, either the sea, a lake or river, where adequate food is available. Eagles are believed to live up to 30 years or more in the wild. Threats and Reasons for Decline Habitat loss over the past 200 years is the factor most consistently associated with declines in eagle populations. Unfortunately for eagles, people also like to live and spend their leisure time near water. In recent decades, the accelerated pace of development along the coast and near inland rivers and waterways is a primary cause of habitat loss, particularly the loss of trees capable of supporting a large eagle nest. Human disturbance can also be a cause of population decline. Activities such as logging, construction, and recreational activity certainly do disturb eagles in some instances. However, the impact of these disturbances is highly variable, depending on the activity, its frequency and duration, its proximity to areas used by eagles, the extent to which the activity modifies the habitat or its use, and timing in relation to the reproductive cycle. Also, some birds are more tolerant of disturbance than others, with adults generally less tolerant than immature birds. Despite this variability, disturbance near nests has caused nesting failures. In the past another key factor in the decline of eagles was human attitudes. Most predators were considered ‘vermin’ and shot. The State of Alaska even offered a bounty for killing eagles.


Finally, the most dramatic declines in eastern eagle populations resulted from environmental contaminants. Beginning in 1947, reproductive success in many areas of the country declined sharply, and remained at very low levels through the early 1970's. After several years of study, the low reproduction of eagles and many other birds was linked to widespread use of the insecticides DDT and Dieldren. These insecticides were used extensively in agriculture and forestry beginning in 1947. As DDT entered watersheds, it became part of the aquatic food chain, and was stored as DDE in the fatty tissue of fish and waterfowl. As eagles and other birds of prey fed on these animals, they accumulated DDE in their systems. Although occasionally causing death, DDE mainly affected reproduction. Some birds affected by the chemicals failed to lay eggs, and many produced thin eggshells that broke during incubation. Eggs that did not break were often addled or contained dead embryos, and the young that hatched often died. Since the ban of DDT and DDE residues in Bald Eagle eggshells have dropped significantly, and a slow recovery of eagle productivity has occurred. Today most eagle populations appear to be producing chicks at the expected rate. Of more recent concern is evidence that lead poisoning may be a significant cause of death in eagles. Chronic low levels of lead can produce nervous system disorders, affect behavior and learning, cause anemia, and increase susceptibility to disease. As laws requiring the use of steel shot to hunt waterfowl become effective, accumulation of lead in the food chain is expected to decline. Electrocution and hits by vehicles as the eagles scavenge road kills collectively kill the most eagles. Ongoing Recovery The greatest challenge for the future will be to prevent further destruction of habitat and retention of sufficient creek and river flows to support a food base for breeding and wintering eagles. Monitoring of nesting success is particularly important in detecting any problems associated with contaminants in the environment. In the urban and suburban regions the loss of nesting trees is paramount. However, just as eagles have adapted to finding good food sources in and around cities, they have also adapted to nesting on artificial structures. Finally, appropriate management of nesting, feeding, loafing, and wintering habitat must be a priority if we are to maintain the current upward trend in eagle numbers. The recent trend of eagles to accept artificial structures for nesting gives some hope for them to reoccupy areas that have suffered major tree losses. Tolerance to Disturbance Eagles fear humans at all times, but will tolerate less disturbance during the nesting season, than at other times of the year. A nesting pair will seek isolation, and any human interference, if prolonged, may drive the birds away from the nest. During the winter, eagles will roost and feed in groups close to human habitation and activity. However, prolonged and repeated disturbances will send the birds on their way in search of another isolated roost or feeding area. Extensive disturbance at these feeding and roosting sites can lessen the eagles’ survival chances as secondary roosts if available, will in all probability not have the vital weather protection that the primary roost provided. Eagles generally choose to roost in large trees in protected places within a few miles of their feeding grounds. Along the river, for example, they most often roost in heavily


wooded, steep-sided valleys, sheltered from northerly winds, or in cottonwoods on islands away from human disturbance. Eagles, being large birds, need large strong trees for nesting, roosting, and perching while hunting. Most coniferous trees have to be over 100 years old and cottonwoods over 50 years old before they can be used as nesting sites for the eagle. Logging and subdivision operations have disturbed or destroyed many nesting territories and potential nest sites, as well as winter roosts. Disturbance at or near the actual nest site up the tree is particularly disruptive. Some eagles have accommodated very effectively in the urban and suburban environment to human activities below a nest. Most eagles nesting within the Metro Vancouver area nest in parks, golf courses or isolated remnant trees throughout the city where the eagles have learned people are not harmful. This accommodation can take eagles a few years. In a number of cases the eagles have sufficiently accommodated to the good city food supply that they have nested in artificial structures when no suitable trees were available. The higher the nest up the tree the less important seems the disturbance below the tree. Nest Choice and Disturbance Intensive recreational or industrial use of land near nests and roosts can disturb the birds. As the human population expands and moves in greater numbers back into the countryside, the eagle is pushed back into smaller and smaller pockets of suitable habitat. Fortunately for humans, eagles are attempting to adjust to our urbanized ways. The critical point to remember is that eagles are very territorial birds, and most breeding pairs return to the same nest site year after year. In areas of great food availability eagles can nest within 250 meters of each other or spread out along a shoreline about 1 to 3 kilometers apart where the resources are fewer. They may use the same nest annually for as many as 35 years, or they may build additional nests in their nesting territory, and alternate the use of them from year to year. If their nests are disturbed or destroyed, the pair may never re-nest again in that tree. The challenge then for the territorial pair is to find another structural support within their territory that will support a nest, so although there are large tracts of wild land away from water available to eagles, the territorial nature of the birds, their precise feeding and nesting requirements, and their past nesting habits, limit the number of suitable nest sites. Known Eagle Pairs in Project Area The Project extent overlaps the territory of at least two known eagle pairs, both of which have nests close to or within the project limits. The first of these pairs is located adjacent to East Esplanade on a strip of Port owned land on the south side of Esplanade. As shown in Figures 1 & 2, for the purpose of this report these will be referred to as the “Esplanade Eagles”.


Figure 1 – Project Extents

Figure 2 – Project East End ‘Esplanade Eagles’

The second pair is located in Moodyville Park on the north side of the existing Low Level Road, as indicated in Figures 1 & 3, and for the purposes of this report these will be referred to as the “Moodyville Eagles”. This pair has available several large old Douglas Firs suitable of supporting a nest. In fact, the nest presently being worked on by them is in a tree adjacent to the tree they previously nested in, according to local eagle authority David Cook. Both the old and new tree appear to be different than the first tree they were observed nesting in about 15 years ago.


Figure 3 – Middle of Project – ‘Moodyville Eagles’

Esplanade Eagles Background The Esplanade pair has attempted, so far unsuccessfully, to nest in two local sites that we know of. The first attempt was about 5 or 6 years ago when the territorial pair started to build a nest on one of the nearby steel cranes, a short distance from the Esplanade nest. This had somehow been destroyed or fell from the structure. Then 3 years ago they started to build the existing nest in the Cottonwood tree on the Esplanade. This nest is still not complete nor very well structurally supported, from the perspective of an Eagle observer the tree could be considered a last resort, with very little alternative nesting habitat elsewhere in the area. The Esplanade eagles have been observed in the area since fall of 2011 when they constructed the nest in the Cottonwood tree. At the time the nest was constructed there was a significant amount of activity but in early 2012 there were some heavy/strong winds, which reportedly damaged the nest. In October 2012, the beginning of the 2013 nesting season, the pair returned to the area and have been observed perching in the Cottonwood tree. The pair regularly occupies the docks, boats, derricks and cranes as territory hunting perches. Both David Cook and David Hancock have examined the nest from the ground and consider it to be in poor condition and precariously placed on branches that are not-very-sturdy. Existing Habitat The Project covers an area which provides good feeding habitat for eagles, as is demonstrated by the two pairs which have territory in the area. Spilled grain from the railcars which service the grain terminals, is a food source for small mammals and birds which supplement fish from the Burrard Inlet as


food sources for the eagles. The mature and tall trees near the Moodyville nest territory, and tall Port buildings and cranes in the Esplanade nest territory provide excellent and multiple perching locations which help the eagles while hunting for food and during feeding. Historical records show that the Burrard Inlet and the area now occupied by the Port was once densely vegetated with mature trees, which provided excellent habitat for eagles to perch and hunt for food, and in which to nest and rear young. During the development and urbanization of the surrounding area most of the trees adjacent to the prime water feeding areas were removed, which reduced the available nesting habitat for eagles. Habitat Mitigation Two mitigation options could be applied in the area of the Project which would encourage eagles into the area. Within the Port lands, there are wide open spaces where no trees currently exist. The installation of an artificial nest would provide eagles with a perch for feeding or nesting. Although this does not replace the trees which would have existed many years ago, it could encourage eagles back into the area. Plantings around an artificial pole and nest would offer some additional habitat for other species. Artificial poles as nest supports are frequently used by eagles in this region. Some examples of artificial nest/perches are shown below:

Away from Port lands the other mitigation measure is to improve existing habitat. Typically this would involve the removal of some of the upper limbs of trees to create an open area and encourage a nest to be built. The felled limbs could also be placed to create a platform that would provide an improved


nesting location. Many trees have had limbs removed and supplemental branches added to facilitate eagles building their own nest. Mitigation Sites A review of the North Shore Trade Area and surrounding lands provided two possible locations suitable for artificial nest/pole/perch installation and two sites where habitat improvements could be made. Figure 4 provides details of these locations. These sites will significantly benefit eagles in the area by providing a suitable nesting site. Figure 4 – Mitigation Extents

Artificial Nest Site 1 The first artificial nest site is on the foreshore adjacent to the existing Esplanade nest on the road to the Richardson Grain Terminal and is very close to the Low Level Road Project area. On the south side of the pole would be the shoreline. This site is nearly equidistance from the existing Esplanade nest and the earlier crane nest, but closer to the water. Figure 5 shows the location of the first artificial nest site. This location would be a possible alternative site for the existing Esplanade eagles, providing easier access to the water and the eagles main food source fish, as well as small mammals and birds which feed on any spilled grain. It is recommended that the pole at this location be 75 feet tall. The territorial pair occupying the Esplanade area have already attempted to nest on such an artificial structure; one of the large cranes. This proposed mitigation site would be a natural selection for them, even putting them closer to their food supply and farther away from possible human disturbance.


Figure 5 – Artificial Nest Site 1

This site is also on the south side of the port security fencing preventing disturbance from the general public. Yet at the same time the nest would be very visible from the Spirit Trail passing to the north. Artificial Nest Site 2 The second location is at Beech Yard, which is east of the Low Level Road Project area and to the north east of the Second Narrows Crossing Rail Bridge. Figure 6 shows the location of artificial nest site 2. This location is outside of the immediate project vicinity but would encourage a new pair of eagles to move into the local area. At the moment this foreshore area is prime eagle foraging habitat but it does not contain any suitable nest trees. This location is both to the east of the Lynn Creek eagles territory (on the west side of the Second Narrows Crossing Rail Bridge) and west of the Maple Flats eagles, the next active eagle territory to the east. The proposed site is sufficient distance so as not to likely interfere with these existing pairs and allow another additional pair to establish a territory in an area that currently has no adequate large trees for nesting.


Figure 6 – Artificial Nest Site 2

Tree Modification Opportunities In addition to the two possible nest/poles mitigation works there are two locations further to the east also outside of the project area, where habitat improvements could be made to encourage eagles into the area. The first is within the Tsleil-Waututh Nation Reserve and opportunities are subject to discussions with the Nation. There are a number of mature trees within the reserve where pruning of upper limbs would make the trees more attractive for eagles to nest. Specific trees have not yet been identified and additional site visits will be required before the exact details can be confirmed. Figure 7 shows the first area where habitat improvements could be made. Figure 7 – Habitat Improvement Area 1

The second site is Cates Park, this site is similar to the Tsleil-Waututh Nation site as there are a large number of mature trees on the east end of the park where pruning and removal of some upper limbs could encourage eagles to nest. Again specific details would require additional site visits which would be undertaken as a second stage to the installation of the posts and artificial nests. Figure 8 shows the second area where habitat improvements could be made.


Figure 8 - Habitat Improvement Site 2- Cates Park

Consideration of Area West of the Esplanade Bald Eagle Territory. At present a well-established pair occupies Mahon Park and hunts the Mosquito Creek Basin and the adjacent waterfront to the immediate west of the Esplanade territory. While land at the waterfront has been suggested as a possible site it does not seem valid to try and squeeze another pair into this Mosquito Creek coastal region at this time. Project Timelines Below are details of the Project timelines and estimated dates by which mitigation measures may be put in place. • May 2012 - MFLNRO contacted and permit application submitted • June 2012 - CNV give approval for Project • December 2012 - Funding agreements signed • December 2012 - CNV Project Agreement signed and design approved • January 2013 - MFLNRO issue permit for tree removal • January 2013 - Tree removal planned • February/March 2013 - Mitigation to be installed Submitted on behalf of bald eagles.

David Hancock

Bald Eagle Biologist

Hancock Wildlife Foundation 19313 Zero Avenue, Surrey BC, V3S 9R9 604-538-1114


APPENDIX

An article by David L Cook (Spring, 2008) “Past, Present and Future Bald Eagle Nest Sites on the North Shore of Burrard Inlet” (attached) provides background on the eagles in the area, it also provides an overview of the bald eagle nests on the North Shore.

5,

Past, Present and Future Bald Eagle NestSites on the North Shore of Burrard Inlet

by David L. Cook

The Bald Eagle (Haliaeetus leucocephalus)has probably nested along the north shoreof Burrard Inlet and its salmon bearingrivers as long as salmon have run in thearea, that is, over the last 4000 years, priorto which Pacific salmon distribution “wasrestricted by the residual effects of theFraser Glaciation” (Lackey (1999). TheDouglas-fir would have been a dominanttree at the time (Whitlock 1992), andwould probably have served as apreferred nest tree then as it does today.

This report describes known Bald Eaglenest sites within the Districts of West andNorth Vancouver and the City of NorthVancouver, between Howe Sound andIndian Arm. One nest in Twin IslandsProvincial Park and a former nest tree inBelcarra Regional Park are included. Allare in Douglas-fir trees; some are oldgrowth, some second growth. For thisreport, the designation “old growth” is asubjective one applied to a tree ofconsiderable girth with deeply groovedbark and thick, usually somewhat twistedbranches. The age of these old-growthtrees is estimated at between 250 and 700years. “Second growth” applies to treesestimated at less than 250 years of age.The second-growth trees described in thisreport are estimated at 100 to 150 yearsold.

In the past, monitoring of Bald Eaglenesting activity on the North Shore hasbeen carried out casually by numerousmonitors, mostly residents living in theimmediate vicinity of each nest. Untilnow, no attempt has been made to collectnesting data into a single publicationaccessible to the public, researchers,municipal governments, politicians andcontractors/developers.

The data collected for this report fall

primarily within the last two decades.Information prior to that time is pooror non-existent. In most cases each nestsite has had or still has one or moremonitors/protectors, many of whomhave been approached. Most werewilling to share the information theyhad, either in the form of written recordsor in anecdotal form. In some caseswhere there was more than onemonitor, the reliability of theinformation could be improved bycross-checking.

In the Table presented on p. 32 anattempt is made to consolidate the data.An account of each nest site is given,including approximate location andnesting history when it is known. TheTable shows nesting activity from theyear 2000 to May 2008, the period inwhich most of the data fall. The limitedinformation available for years prior tothe year 2000 and other information ofinterest for each nest site are given inthe narrative description for each nest.

Names of monitors and exactlocations of nests have been withheldfor privacy and security reasons. Thatadditional data will be made availableto the Wildlife Tree StewardshipProgramme (WiTS). The WiTSprogramme is an environmentalstewardship programme of BC Nature,(the Federation of BC Naturalists orFBCN) that aims to create, co-ordinate,and assist a network of communitystewards interested in conservingwildlife tree habitats through volunteermonitoring, landowner agreements,and community education in BritishColumbia. The recently appointed WiTSCoordinator is Ian Moul, [email protected]. The WiTS website is

Spring 2008, 37 (1) 27

www.wildlifetree.org.A discussion follows on the pressures

that Bald Eagles experience when nestingon the North Shore now and in the future,together with the possible consequencesof those pressures.

Description of Nesting Sites:

Fifteen nesting sites are describedbelow, Of these, 11 sites have shownactivity in the last few years and shouldbe considered active. Numberscorrespond to those on the location map,p.3O.

1. Ansell Place, Sunset Beach. WestVancouver: Located in what is probablyan old-growth Douglas-fir west of andbelow the pull-out south of the AnsellPlace turnoff on Highway 99, at the edgeof the B.C. Rail alignment. Debris at thebase of the almost inaccessible tree hasincluded numerous feathers and birdbones, a dried carcass of a young eagle

and a stuffed toy Santa Claus. This is anunusual nest site in that the nest is slightlybelow eye level when observed from thepull-out so that it is possible to lookpartly into the bowl of the nest.However, if a very young eaglet iscrouched low down in the cup of the nest,it may not be visible. While the tree itselfwifi not be directly impacted by highwayimprovement, the potential fordisturbance due to noise is high. As statedin the B.C. Government’s Fact Sheet “Seato-Sky Highway Improvement Project”(2003), the “new clearing and grub lineindicated on the maps will come withinapproximately 30 m of the nest tree. Inaddition, Rock Cut No. 9 is immediatelyadjacent to the nest site. MWLAP[Ministry of Water, Land and AirProtection] generally requests a 50—100m radius buffer, assured from the baseof the nest, between the tree anddisturbance, excluding the potentialdisturbance from blasting. The risk ofsuch activities, particularly blasting, is

Ansell Place nest, April 2008. Yet another attempt to nest in the presence of major disturbancesassociated with the Sea to Sky Highway Improvement Project. Photo by Susan Cameron.

28 Discovery

that the nesting pair might abandonnesting attempts, which extend on thesouth B.C. coast from initial nestoccupancy (early February) to fledgingnate July). Exact dates and exclusion areaaround the nest will arise fromdiscussions with MWLAP staff.” Theeagle pair at this nest made a valiantattempt to nest in 2007 in a scenario ofblasting and rock pile removal near theirnest. The nesting, however, ultimatelyfailed. In 2008 they are repeating thiseffort and so far succeeding in spite ofrepeated disturbance due to highwayconstruction activities near the nest.

2. Arbutus Rd. West Vancouver: Anactive nest existed, from before 1966 to2001, in an old-growth Douglas-fir on aprivate property on Arbutus Road,Whytecliff park, West Vancouver.(Trudel Kroecher, personal communication). In the Greater VancouverNesting Survey Report of 1988, the nestwas described as “active,” with a fledgedjuvenile recorded. The nest probablyremained active until about 2000 whenmajor construction in the area began. InMarch 2006, the old-growth tree(together with a nearby old-growthperch tree) was cut down for theexpansion of a driveway.

3. Lighthouse Park, West Vancouver:Bald Eagles have nested in LighthousePark for many years. Currently there isone known active nest site in an old-growth Douglas-fir. There are usually avariety of bird carcasses and bonesbeneath the tree, e.g., those of Barred Owland gull. A second old-growth Douglas-fir about 150 m away from the nest tree,where bones and feathers still litter theground, was probably a former nest site.This former nest tree is located close to atrail and may have been vacated becauseof increasing human and dog trafficbelow it. Fortunately, Lighthouse Parkis well stocked with suitable nest trees.

If the existing pair continues to breed, itwill be interesting to see if the Park cansustain more than one nesting pair.

4. Piccadilly Park, West Vancouver:The nest is in an old-growth Douglas-firwith a broken top, one of a grove of old-growth Douglas-firs, all with brokentops. The tree also contains a PileatedWoodpecker nest two metres from its topand a Northern Flicker cavity seven mfrom the top (KS Biological Services2005). Blasting and tree removal in 2005on adjacent residential lots may havediscouraged the eagles from nesting in2006 or 2007. Considerable blasting forhousing development began again inMarch 2008.

5. Marine Drive, West Vancouver:Like so many of the Bald Eagle nest treeson the North Shore, this nest is in abroken-topped old-growth Douglas-fir.Broken tops (lost leaders) removed bystorms or cut for views create a suitableplatform for Bald Eagles’ nests which canweigh up to 1000 kg. Nesting activity atthis site was recorded in 1988 (GreaterVancouver Nesting Survey 1988). Moreconsistent records have been kept since2003 (see Table, p. 32).

6. Mahon Park, City of NorthVancouver: Located in the forestedsection of Mahon Park in a large Douglas-fir with a broken top.

7. Moodyville Park, City of NorthVancouver. The nest is in a second-growth Douglas-fir with a broken topand new leader. The eagles feed almostexclusively on pigeons, hundreds ofwhich feed on grain spilt duringoperation of the nearby grain elevators.Although not monitored on a regularbasis, the impression has been gained thatthis is a very successful nest site becauseof the protected location and the ampleclose food source.

Spring 2008, 37 (1) 29

8. Riverside Drive, North Vancouver:The nest is on private property in asecond-growth Douglas-fir that, like theMarine Drive nest, lost its leader. It wasoriginally built in the fall of 2005, butsuccessful nesting was not observed until2007. The remains of duck, crow, pigeonand salmon have been found beneath thenest.

9. Maplewood Flats, District of NorthVancouver: In April 2008 an adult BaldEagle was observed adding to a nest in asecond-growth Douglas-fir. A singlecrow harassed the adult during the one-hour period of observation during whichthe eagle returned three times with nestmaterial. Eroded food pellets beneaththe nest suggest that this nest was usedin 2007 and possibly 2006. While anexcellent location for food supplies, thetree looks unsuitable for holding a nest;the branch on which the nest isconstructed seems unlikely to hold it asthe adults add nest material in futureyears. The nest is also positioned in avery open area. In May 2008 no eagleactivity could be detected.

10. Windsor Secondary School,District of North Vancouver: The nest isin a second-growth Douglas-fir that haslost its top and developed new leadersbetween which the nest is positioned.Nest material is caught in branchesbelow the nest. Eroded pellets at the baseof the tree indicate that this nest was usedin former years. Remains of gull werenoted on the forest floor below the nest.Activity has not been detected in 2008.

11. Roche Point Forest, District ofNorth Vancouver: This site has thelongest and most complete recordedhistory of any on the North Shore.Nesting was attempted in 1987 and 1988but was unsuccessful possibly due to toomany visitors resulting from publicityabout protecting the nest tree fromdevelopment. After 1988, following anice storm, the nest fell out of the tree andmonitoring stopped because it wasassumed that the eagles would notreturn. Because the tree was remote, onlyvisible from one location and difficult toaccess, the memory of its existence faded.

30 Discovery

The location of the tree was shown to meby District of North Vancouver SectionManager Kevin Bell in 1999. In the year2000, I visited the tree during nestingseason and was able •to establish thatnesting had resumed. Nesting wassuccessful every year following that until2007 when results were inconclusive. Thenest fell out of the tree soon after August2007 but has been rebuilt in the same treein time for the 2008 nesting period. Bone,feathers and flesh remains at the base ofthe tree over the years have includednumerous species of birds (probablymostly acquired from Maplewood Flats),a leg band from an osprey that had beenbanded near Camden in WashingtonState in 1998, a grey squirrel and salmon.Other items included plastic garbagebags and a stuffed toy orca (compare thestuffed Santa Claus at Ansell Place). Atrend towards fledging earlier each yearhas been observed at this nest site: on 31August 2000, 19 August 2004, and earlyAugust 2006. Offspring from this nestmay have established the MaplewoodFlats and Windsor High School nests.

12. Deep Cove, District of NorthVancouver: An old-growth Douglas-firwith a broken top in Cove Forest Parkabove Deep Cove a few yards east(downhill) from the Baden Powell Trailwas probably an abandoned nest site. Inthe year 2000, bone material on theground indicated that this tree had beenused as a nest tree in the recent past. Nobone material remains today. It ispossible that the tree was abandoned asa nesting site because of increased use ofthe Baden Powell Trail. The emergentbroken crown of this tree can be seenfrom Panorama Park in Deep Cove.

13. Brighton Beach, District of NorthVancouver: Information from variouspeople suggests there may be a nest inthis area. However, it is possible thatthese reports are not of a nest but of eagles

attracted to the area by salmon carcassesleft by local residents.

14. Twin Islands Provincial Park:Although not visited by me, a nest hasbeen confirmed at this location by a B.C.Parks employee. The pair from this nestmay be the eagles being fed at BrightonBeach located 1km to the northwest onthe western shore of Indian Arm.

15. Admiralty Point, BelcarraRegional Park, Belcarra: An old-growthDouglas-fir between the trail and thebeach at Admiralty Point was reportedto contain an active nest in 1977 (SigmaResource Consultants Ltd: 1977). Thedescription and location of the tree wasconfirmed by the writer during visits tothe area in 2006 & 2007. No nest or eagleactivity was observed during these visits.

Discussion & Conclusions:

This study helps to clarify the nestinghabits of Bald Eagles on the North Shore,makes some general observations andraises a number of questions fordiscussion:

The history of Bald Eagle nesting onthe North Shore, particularly in recentdecades, seems to have been a strugglebetween finding suitable nest treeswithin convenient distance of a foodsource while at the same time learningto tolerate increasing disturbance relatedto human activities.

The selection for some of the morerecent nests (Windsor High School andMaplewood Flats) of second-growthDouglas-firs with their weaker branches,as opposed to old-growth Douglas-firswith their stronger branches, suggests acurrent shortage of suitable trees for nestconstruction near favourable foodsources on the North Shore. It furtherleads to the possibility that we are seeingthe beginnings of a new phase of BaldEagle nest construction. If the North Shore

Spring 2008, 37 (1) 31

population of Bald Eagles continues toincrease, as seems to be the case, thesupply of suitable Douglas-firs will beinsufficient. Eagles like to return to theirformer nests, and over years, wifi buildthem up until they become large andheavy. As more and more unsuitabletrees are selected, the consequence mightbe short-lived nests, as the increasingweight of the nests will cause the weaksupporting limbs to fail. My predictionis increasing relocations in the future.This could result in increased expenditureof effort for the parent birds and couldresult in failure of breeding, particularlyif the nest falls from the tree at aninopportune time. As nest trees areremoved, particularly in West

Vancouver where there are norestrictions for tree removal on privateproperty, the North Shore population ofBald Eagles may reach a plateau and evendecline as suitable trees are removed.

In B.C., the number of fledges for eachsuccessful nesting is reported to be about1.5 for 1994 (Blood & Anweiler 1994). Thisaverage approximates that of the RochePoint nest (the nest with the mostcomplete record) over a monitoringperiod of 7 years.

Eagles often build more than one nest,but alternate nest sites located to dateare few in number. The former nest treeabove Deep Cove and an old site inLighthouse Park should not be classedas alternate nest trees but sites

‘Jo Site 90 2001 2002 2003 2004 2005 2006 2007 2008AF A F A F A F A F A F A F A F A F

lAnseilPiace y 7 y ? y 7 y 7 y I y 0 y1 1 1 2

2 Arbutus Rd. y 7 y 7 n 0 n 0 n 0 n 0 Tree removed fordriveway imorovement

3 Lighthouse y I yPark

4 PiccadillyPark y 7 ? ?y ? n 0 n 0 n 0 L —

5MarineDrive 1lLlnOLl2L6 Mahon Park y 2 y 7 y

7 Moodyville y 7 y 7 y 7 yPark I

8 Riverside y I yDrive

9 Maplewood ? 7 y

10 Windsor 7 7Secondary ySchool

liRochePoint y 2 y I y 2 y 7 y 2 y 2 y 7 y 7 y‘ Forest

12 Deep Cove Probably used as a nest tree prior to about 199513 Brighton No confirmed nest or tree. Possibly an artificial feeding site only.

Beach14 Twin Islands This site not yet visited by the author15 Belcarra Site visited by author 2006 & 2007. No nest or eagle activity observed.

A = Active nest. Adult/s on nest or in nest tree.F = Fledged. Number of eaglets fledged.

= Unknown71 ,?2 = Doubtful data.Where there is no data there was no monitoring.

32 Discovery

abandoned in the past probably due toincreased human and dog traffic beneaththem.

Very little in the way of consistentnesting records have been kept for BaldEagle nest sites on the North Shore. Thisarticle is intended to serve as a catalystfor improved awareness and monitoringof nest sites so that they may be betterprotected.

The scenario between residents andthe authorities that has played out at theAnsell Place nest site (see p. 28) over thelast three years as a result of the Highway99 upgrade could be used as a guide forthe way in which various levels ofgovernment, contractors and the publicshould work together when a Bald Eaglenest exists in an area to be developed.

The Bald Eagle is a high-profile specieswith great public appeal because of itssize and beauty, and can be used as anentry point for nature education.

There are 11 more or less active nestsbetween Roche Point Forest and AnsellPlace, a distance of 38 km, with anaverage of 3.45 km between nests. Thisdistance is thought to be a function ofavailable nesting trees, food supply,competition and population density, andat this time matches the average for B.C.(Blood & Anweiler 1994). However, as issuggested by the nests clustered aroundthe Roche Point Forest nest, there seemsto be some preference for birds to returnto the area where they were fledged. Theconsequence of this may be pockets ofhigher nest density.

The author’s interest in the Bald Eagles ofthe North Shore began in 2000 when hewas shown a Bald Eagle’s nest in amagnificent old-growth Douglas-fir inRoche Point Forest. This experience raisedmany questions in his mind about thepopulation ofBald Eagles on the NorthSlwre, particularly the need to conservetheir nesting trees and habitat. The author’s

parallel study of the old-growth trees andforests of the North Shore provided anopportunity to discover new nest sites andobserve the dynamics of the resident BaldEagle population. This article summarizesthe work to date and sets the stage for thenext phase of study, which will involve theWildlife Tree Stewardship Programme.

References

Blood, D.A. &G.G. Anweiler. 1994. Statusof the Bald Eagle in British Columbia.Wildlife Working Report No.WR-62.Wildlife Branch, Ministry ofEnvironment, Lands & Parks, Victoria,B.C.

Greater Vancouver Nesting Survey. 1988.Nesting survey of Greater Vancouverarea conducted by Wildlife Branch,Ministry of the Environment, NorthVancouver Ecology Centre and theVancouver Natural History Society.

Hancock, D. 2003. The Bald Eagle ofAlaska,BC and Washington. Hancock House.

KS Biological Services. 2005. A letteroutlining implications of observedbird activity for type and timing ofconstruction activities near the AiisellPlace (WP2) Bald Eagle nest.

Lackey, R.T. 1999. Salmon policy: Science,society, restoration, and reality.Renewable Res. Jour. v. 17(20), pp. 6-16.

Sea-to-Sky Highway ImprovementProject. 2003. Volume 2, Section A:Wildlife & Vegetation, Ministry ofTransport.

Sigma Resource Consultants Ltd. 1977.Resource master plan study, BelcarraRegional Park. For Greater VancouverRegional District.

Whitlock, C. 1992. Vegetational andclimatic history of the PacificNorthwest during the last 20,000 years:Implications for understandingpresent-day biodiversity. NorthwestEnvironmental Journal, v. 8, pp. 5-28.

Spring 2008, 37 (1) 33

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Report on the Low Level Road Project Regarding Bald Eagle ... · Since the ban of DDT and DDE...

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