IMPACT OF SEA PADDLING ON MARINE BIRD POPULATIONS

DUTIES AND RESPONSIBILITIES OF GUIDES

                                               
By Tom Pogson, Alaska Canoe base
http://www.alaskakayakschool.com/news.htm.
 tomp@alaskapaddler.com

 

1. There are more humans alive today than in the history of the Planet.

 

2. Man’s modern utilization of marine resources is exploitative, not renewable.  Best indicators are the state of marine fisheries resources – measured as a function of catch per unit effort and serial collapse.

 

3. Populations of approximately one-third of the Earth’s 9,000 avian species are endangered, threatened, or in serious decline.

4. Birds are sensitive indicators of environmental changes.

 

5. Marine birds include a diversity of types of birds (taxa) with a diversity of life-history strategies:

Year-round residents: Alcids (guillemots, murres, razorbills, puffins), boobies, petrels, fulmars, shearwaters, gannets, alabatross, frigatebirds, and tropicbirds and coastal populations of gulls, terns, pelicans, some waterfowl, etc. Also includes some shorebirds, such as turnstonesn and oystercatchers.

Seasonal residents: many species breed on land and often near near freshwater environments and winter at sea. For example, many waterfowl (scoters, eiders, scaup, ring-necked ducks, canvasbacks, redheads, oldsquaw, etc.), some species and populations of gulls and terns, and many shorebirds, such as turnstones, sandpipers, tatlers, curlews, sanderling, dunlin, dowitchers, phalaropes, godwits, etc.

 

6. The use of marine environments by birds follows three patterns:

Pelagic – use of the open ocean’s surface and water column.

Near Shore – use of the ocean’s surface and water column in the near shore environment.

Shore or littoral – use of the immediate shore within the tidal zone and the spay zone.

 

7. Birds are probably best known for their migratory habits, which differ widely. Migrations are usually characterized by long-distance movements to and from breeding areas and wintering areas.  Migrations to molting areas are also of critical importance.

 

8. In general, individual birds are extremely habitual and have a strong habit of returning to use the same sites from year to year and from day to day. This attachment allows the familarization with a predictable environment that serves their needs and promotes their success at feeding, breeding, molting, etc.

 

9. Man’s overwhelming impact on bird populations is negative. Man has been systematically altered avian habitats, and this alteration is leading to the loss of global avian abundance and diversity. Any activities of paddling groups that have negative effects on bird populations are additive with long-term negative cumulative impacts already  “in place”.

A few species seem to have benefited from man’s activities: Starlings, House Sparrows, Canada Geese, Snow Geese, Rock Doves, Cowbirds, Ravens, Gulls, etc.

1. Basic Avian Life Cycle includes: breeding, molt, migration, and winter/non-breeding season residence.

10 . Breeding includes – courtship and pair bonding, incubation, hatching, brood-rearing, fledging
Molt is the systematic replacement of feathers by birds. These are complex and diverse strategies.

 

11. The impact of sea paddling groups on bird populations is a complex interaction between many factors (here are some):

a .  Type of disturbance.
Scare birds
“Move them around”
Kill the birds
b. Life history cycle in which the disturbance occurs.
        Breeding Season – courtship, egg-laying, incubation, hatching, brood rearing
        Migration
        Winter
        Molt
* The season in which the disturbance takes place is important. Disturbance during the breeding season is likely to have a greater impact than disturbance during the non-breeding season. Mortality rates of birds prior to reaching breeding age tend to be high, but given that the stars are lined up and a breeding population is going to have an otherwise successful breeding season, disturbance of a breeding colony by a paddling group or paddling groups could make the difference between a “good” breeding season and a “bust”.
c. Frequency and intensity of the disturbance.
        Single event
        Repeated Events
        Light disturbance – i.e., roosting bird lifts its head to check you out
        Heavy Disturbance – i.e., birds fly away as you approach
d. Effect of the disturbance.
        Birds move short distance.
        Birds disturbed and predator(s) take advantage of disturbance to kill birds you have disturbed.
        Scare incubating bird off nest – predator destroys nest.
        Scare attending adults away from brood, predators attack and kill young.
        You step on and crush nest while leading group on a hike.
        You visit a colonial nesting bird colony and gulls, ravens, and other predators have a feast!
You and your group have lost your food to a bear and come across a bird colony
     and decide to feed on the birds, eggs and young in the colony.

 

e. “Scale” of the disturbance.  This is the most important factor determining the impact we have on bird populations, and it is the most complicated to understand! It can be summarized as the “depends” factor. Here are some examples.

1. You are the only paddler to reach a remote island in the Canadian arctic that is the nesting site for 10,000 pairs of Snow Geese, and you have run out of food. It is early in the year and it is the egg-laying period. You walk into the colony causing massive disturbance to get some eggs so that you can eat and replenish your energy. The colony is spread out over 4 square miles and you collect 1,000 eggs and manage to club 500 adults to death and you have replenished your food for the rest of your trip.

Is your impact on this population significant?  What do you need to know to evaluate your impact?

1. You have led 100 groups of 10 paddlers each to an off-shore island that is the sole nesting site of an endangered species of tropical gull in the Sea of Cortez. You insist on taking all groups ashore to view the nesting colony during the peak of nesting season, and you always insist on taking your clients ashore during the heat of the day when the Ravens are out foraging. The Ravens have learned to follow you and your groups around and they are taking large numbers of eggs and young each time you visit the nesting colony?

Is your impact on this population significant?  Why?

Birds have been an important resource as food and clothing for man for thousands of years? Even in the late 20th Century, populations of hunted species have significantly recovered following measures to restrict hunting and adjustments to hunting regulations.

Natives on the outer Yukon-Kuskowkim Delta in Alaska built their culture around the harvesting of birds for food and clothing for thousands of years.  It wasn’t until the late 20th Century that these subsistence harvesting activities, in combination with intense hunting pressure in the “lower 48” led to the near collapse of the most diverse goose nesting assemblage in the world. Changes in native infant survival leading to increasing “subsistence” pressure, in combination with the advent of “improved” technology resulted in “over-harvest” and severe population declines. Goose populations numbering in the hundreds of thousands reduced to tens of thousands, and recovered to the tens of thousands in 10-15 years of modified hunting regulations.

Seabird populations tend to have low reproductive rates, and high adult survival. This means that they live a long time and have a small chance of successfully breeding in any given year.  In general seabird population numbers are sensitive to changes in adult survival, rather than to changes in reproductive rates, which are almost always low.3

 

ABSOLUTE NO-NO’s as the leader of groups

1. 1. Approaching a colonial bird nesting area during the breeding season, either on foot or on the water, especially repeatedly during the course of the breeding season

   2.   Approaching waterfowl broods, i.e., eiders, when there are Greater Black-backed or Herring Gulls in the area.

   1. Approaching cliff nesting seabird colonies from the water, especially during incubatio

THE BOTTOM LINE

As a guide that will be leading groups into areas used by seabirds, it is your responsibility to know and understand the following:

1. What species are present in the areas you are guiding in?

1. What is the status of the populations in the areas you are guiding in?

1. How can you eliminate or minimize the impact of your activities on the bid populations in the areas you are guiding in over the entire season and over the long-term.

1. What is the breeding season, brood rearing season for the seabirds in your area?

 

Establish and develop relationships with wildlife management agency personnel responsible for managing and monitoring that numbers and population trends of sea birds in your area.  Stay abreast of changes in their numbers and of the history of the populations by having regular communications with wildlife agency personnel. Invite wildlife biologists to give guides orientation talks sensitizing them to the local conditions.